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Resolved 1G 6 bolt timing belt tensioner oil leak

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all black 4G63

Proven Member
254
43
Aug 5, 2019
Chicago, Illinois
Does anyone have a final remedy to address the oil leak from the lower timing belt tensioner bolt on a 6 bolt? (photo attached)

I have read post, but wanted to get a fresh suggestion as most post are from early 2000's

I have used 3 bond on the bolt, but obviously it still leaks.

Also is there any other areas for potential oil leaks behind the timing belt cover that I should be aware of?

Thank you for the support

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Solution
UPDATE!

Well the f***ing leak is gone. I replaced the seal and sprocket and drove the car hard... there's no oil on the belt anymore and the rest of the timing pulleys are dry.
What's funny is my POS Jayracing ALT relocation bracket (Bottom) finally cracked during the drive so I couldn't go too far, but everything looks OK for now...

"We're on Boost" What I think the lip on the replacement pulley is for is for when you slide the pulley on, the lip on the edge allows the seal to be wrapped around the surface without folding possibly>?

Why all of this occurred. Well.....It may be possible that the original front case/oil pump assembly went through a rough beginning....What I mean is that I think I may have over tighten the timing...
Well I swapped the OFH and bypassed the cooler. Oil pressure is the same. nothing f***ing changed..........f*** this car!! this is a goddamn joke for real my motor has to be fuvcked. You can see the oil being slung on the kicked out sump of the oil pan

At 4500 RPM im at 95 PSI 3000 RPM is like 76 PSI HOT f***ING ENGINE

I have a picture of the porting i did to the previous OFH is it possible I need to do more?

The other picture is the swapped OFH and bypass of cooler

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if the pressure regulator is not functioning than this would explain everything.... i hope.
So you haven't checked that yet? That's the pressure relief valve that I have been mentioning and that should be the first thing you should check. Like the video below.
If there was a restriction in the cooler itself I don't think that would cause my high oil pressure problem because of the bypass and the fact that my oil pressure on cold start is over 100 PSI and stays there for quite a while (90-99PSI) this should be during bypass (cold engine).
As I mentioned that if the oil cooler is clogged/restricted badly, it would affect when the oil temp is hot. When the oil temp is low, not much oil goes through the oil cooler. Most of oil bypass the cooler. It's kinda rare but if this is the case, when the oil temp is high, the oil pressure may be higher than when it's cold.
However, the oil leaking out of the top of the cover occured before taking the engine to the machinist.
Wait a sec, so you had this issue before rebuilding the engine? Why did you rebuild the engine?
Now I start thinking something different. Maybe the issue is an assembly error. Perhaps you installed main bearings up side dowm then blocked off main oil feed holes.

Perhaps a ignorant question but are you putting the front case gasket on dry and have you checked the cover and block for flatness?
Steve, yeah I thought that too. And I already asked him earlier. But I don't know if he inspected or not.

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Steve, yeah I thought that too. And I already asked him earlier. But I don't know if he inspected or not.

I saw the question but I never saw the specific answer. I thought I read that at least once there was a mention of a "little RTV" which would be a big problem but I get confused and sometimes fix threads in my head.
 
Perhaps a ignorant question but are you putting the front case gasket on dry and have you checked the cover and block for flatness?
I put it on dry the first time, then the second time i used 3 bind on both sides. I checked for flatness by hand.............. however, Im starting to think the oil is not coming from there anymore I looked with a mirror and that spot is dry but oil is slinging everywhere

So you haven't checked that yet? That's the pressure relief valve that I have been mentioning and that should be the first thing you should check. Like the video below.

As I mentioned that if the oil cooler is clogged/restricted badly, it would affect when the oil temp is hot. When the oil temp is low, not much oil goes through the oil cooler. Most of oil bypass the cooler. It's kinda rare but if this is the case, when the oil temp is high, the oil pressure may be higher than when it's cold.

Wait a sec, so you had this issue before rebuilding the engine? Why did you rebuild the engine?
Now I start thinking something different. Maybe the issue is an assembly error. Perhaps you installed main bearings up side dowm then blocked off main oil feed holes.


Steve, yeah I thought that too. And I already asked him earlier. But I don't know if he inspected or not.

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I swapped OFH housings and it made no difference. The OFH housing i used to swap with came off of a running engine with no issues and I didnt take it apart

I assembled the engine the first time. The machinist that mostly builds 4G63's assembled it this time around. They are a reputable shop that mostly do 4G's I can't image they put bearings in upside down plus im sure my engine would smoked by now i have almost 200 miles on it.

Perhaps a ignorant question but are you putting the front case gasket on dry and have you checked the cover and block for flatness?
I didn't use any precision tools to check to see if the front of the block is flat just by hand.

I live next to boostin performance and they said the high oil pressure is more or less normal as they have had engines do the same thing without oil leaking.

I am starting to think that the oil leak is from somewhere else..... i used a mirror today and the area at the top of the front cover is dry now. WTF
everything on this engine us new. The CAM seals, the front crankshaft seal, oil pump drive seal, balance shaft removed OEM plug, the only thing that's not new the f***ing valve cover gasket but I swear that area is dry.

PLEASE GOD
 
Shot in the dark here, but did you drive the cam seals in after you torqued the cam caps down in accordance with the FSM? Or did you install the seals and then tighten the cam caps over the seals? The seals like to squish out if you installed them user the latter procedure… and that could cause cam seal leaking… I’m only bringing this up because you don’t think the leak is from the front case anymore…
 
I assembled the engine the first time. The machinist that mostly builds 4G63's assembled it this time around. They are a reputable shop that mostly do 4G's I can't image they put bearings in upside down plus im sure my engine would smoked by now i have almost 200 miles on it.
I see, yes this is probably not the case. I asked you just in case. but actually the engine would run like that a couple of hundred miles without making noise. This is the worst case, so should be the last thing you should be worried about.
I live next to boostin performance and they said the high oil pressure is more or less normal as they have had engines do the same thing without oil leaking.
Yes that's what I have been telling you that you seem to have higher oil pressure but generally it's not that high as it can blow the gasket. I had had higher pressure without a drop of oil leak. That's why first I doubt some sort of sealing issue or the oil is actually coming from somewhere else, such as head gasket sealing that I mentioned earlier.
I didn't use any precision tools to check to see if the front of the block is flat just by hand.
Do you have a feeler gauge? If you do, try to insert it between the front case and the block.
 
Shot in the dark here, but did you drive the cam seals in after you torqued the cam caps down in accordance with the FSM? Or did you install the seals and then tighten the cam caps over the seals? The seals like to squish out if you installed them user the latter procedure… and that could cause cam seal leaking… I’m only bringing this up because you don’t think the leak is from the front case anymore…
Thanks for the reply,

yes i torqued first then installed the seals using the Miller special seal installer. I do not see oil in that area, but who knows anymore..

I see, yes this is probably not the case. I asked you just in case. but actually the engine would run like that a couple of hundred miles without making noise. This is the worst case, so should be the last thing you should be worried about.

Yes that's what I have been telling you that you seem to have higher oil pressure but generally it's not that high as it can blow the gasket. I had had higher pressure without a drop of oil leak. That's why first I doubt some sort of sealing issue or the oil is actually coming from somewhere else, such as head gasket sealing that I mentioned earlier.

Do you have a feeler gauge? If you do, try to insert it between the front case and the block.
Thanks you for reply.

The area at the cover/block that was wet before is now completely dry. I can see it directly with a mirror. This tells me that the oil just accumulated there before after driving it and I missed diagnosed it as a poorly sealing front cover. I can't f***ing believe this shit. There's only a couple of areas the oil can leak from/. The head gasket is new (HKS MLS) as well. the block was check for flatness and the head as well. I can clearly see the head gasket area and its definitely dry. The only thing I am reusing is the valve cover gasket. everything else is NEW. I will add a photo of the front belt cover which outlines the leak area. it was worst before this is accumulation of 160 miles

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WHAT A SECOND COULD THIS BE THE ISSUE????

If you see my picture of the front timing belt cover it looks like the oil is leaking from the oil pump sprocket....Well maybe it is, but how could that be it is f***ing new..the oil pump, the front cover and the seal are all new. And this leak has been the same before and after front cover replacement.
Well maybe the high oil pressure and the fact that porting the regulator drain back made no difference at all is because the little oil pump drain back port on the front cover is being block by the Moroso oil pan and felpro gasket????? anyone heard of this????

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I also should mention that when I replaced my front cover the first time the oil pump driven gear shaft was f***ed and the pump had to be smacked out with a hammer. I just always thought this was because of over tightening the timing belt, but maybe it is because of that drain hole being blocked and caused high pressure and cocked the gear over?????
 
WHAT A SECOND COULD THIS BE THE ISSUE????

If you see my picture of the front timing belt cover it looks like the oil is leaking from the oil pump sprocket....Well maybe it is, but how could that be it is f***ing new..the oil pump, the front cover and the seal are all new. And this leak has been the same before and after front cover replacement.
Well maybe the high oil pressure and the fact that porting the regulator drain back made no difference at all is because the little oil pump drain back port on the front cover is being block by the Moroso oil pan and felpro gasket????? anyone heard of this????

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It's still one of possibilities, since oil leak is hard to pinpoint because many parts are rotating and spread the oil everywhere. Sorry totally no offense but guesstimation is a big enemy. So you should physically inspect all possibilities and kill it one by one.

In case if the oil comes from the oil pump sprocket seal, there are some possibilities I can imagine.

1. The seal was not installing properly.
2. The sprocket was not installed properly.
3. The oil pump sprocket shaft sleeve got deformed oval and the shaft doesn't sit straight. In this case most likely you ran the engine with too much tension on timing belt.
4. That pinhole can be a possibility but I guess it is unlikely in general.
 
The leak was there before and after the OEM front case install. The OEM case comes with the seals installed.
f*** this I need to walk away I’m seriously loosing it.

what really blows my mind is the fact that I ported the OFH housing and it made NO difference at all. There must be a restriction somewhere...?
 
We even don't know yet if the leak is caused by the oil pressure or just a sealing issue or from somewhere else. You have to figure out from where first and then what causes the leak if by the high oil pressure or sealing issue. If the front case is removed now, should check everything that have been mentioned earlier. I know it's PITA but no guesstimation even it looks dry, touch physically to confirm. And if I were you, also I would make sure if the oil pressure sensor is reading correctly or not.

If there is a restriction somewhere, that would be the main bearings installed in wrong position like I mentioned earlier or oil squirters are stuck or foreign object in oil passage or the pressure relief valve is stuck or its dump hole is blocked somehow, etc. But you know even if there is a restriction somewhere post oil pressure sensor, I don't think you get abnormal high pressure that can blow the front case gasket if the pressure relief valve is working as it should.
 
We even don't know yet if the leak is caused by the oil pressure or just a sealing issue or from somewhere else. You have to figure out from where first and then what causes the leak if by the high oil pressure or sealing issue. If the front case is removed now, should check everything that have been mentioned earlier. I know it's PITA but no guesstimation even it looks dry, touch physically to confirm. And if I were you, also I would make sure if the oil pressure sensor is reading correctly or not.

If there is a restriction somewhere, that would be the main bearings installed in wrong position like I mentioned earlier or oil squirters are stuck or foreign object in oil passage or the pressure relief valve is stuck or its dump hole is blocked somehow, etc. But you know even if there is a restriction somewhere post oil pressure sensor, I don't think you get abnormal high pressure that can blow the front case gasket if the pressure relief valve is working as it should.
based on the timing belt cover oil splatter pattern it really seems like the source of the leak is the oil pump sprocket. It is literally the only think I have not replaced. Has anyone ever experienced this? If so is it possible to remove and install with the front case on?

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based on the timing belt cover oil splatter pattern it really seems like the source of the leak is the oil pump sprocket. It is literally the only think I have not replaced. Has anyone ever experienced this? If so is it possible to remove and install with the front case on?

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Yes, you can totally remove the oil pump sprocket with the case on. First remove the tb that’s on there. Then, wrap a junk tb (if you happen to have one sitting around) around the sprocket and hold the sprocket (with belt wrapped around it to prevent sprocket damage) with a large set of pliers, while removing the sprocket nut with a 14mm impact socket.
Before you do that though, as I recommended before, consider spinning the oil pump with a drill to see if you can replicate the leaks with everything out of the way. If the leak is coming from the pump sprocket, then you would know for sure while spinning it with a drill. And if it turns out to be just a bad seal somewhere else, I bet spinning the pump with a drill would find it.
I think my electric drill is rated at like 2,500 rpms. You were seeing like 76psi hot at only 3,000 rpms. I would wager that if your relief valve wasn’t working that spinning it using drill speeds with cold oil that your leak would materialized and you would see it. That’s just my two cents.
 
based on the timing belt cover oil splatter pattern it really seems like the source of the leak is the oil pump sprocket. It is literally the only think I have not replaced. Has anyone ever experienced this? If so is it possible to remove and install with the front case on?

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If you believe that the leak occurred at the oil pump sprocket seal, please make sure on the sprocket where contacts with the seal if the surface is smooth and totally round, no crack no rust. and also the pump drive gear shaft sleeve on the front case is totally round when you remove the seal. If you see it's oval, you have to replace the front case (since you mentioned it's new, I don't think this is the case).
To replace the seal can be done with the front case on the block. That seal seals the sprocket so if remove the sprocket you will have enough room to insert an angled pick or some sort of thing.
 
Is it possible that all this is caused by the use of a stub shaft in place of the eliminated balance shaft?

has anyone had problems with oil leaks caused by eliminating the balance shafts and using the MITSU stub shaft?

this problem with the oil leak has been there before and after front case replacement. And every time the front case is replaced it comes with new OEM seals already installed.

my last case had an issue when I removed it and inspected it. The oil pump drive gear shaft was totally worn out and I needed to use a hammer to remove the drive gear shaft out of the case. The shaft wore terrible grooves into the case.

The front case only had 500 miles on it (this was a new case as well). Could this all be because the timing belt was too tight?

Well I can ensured you the timing belt was not over tightened the second time around, but still got the leak.

I’m certain now the leak is coming from the oil pump sprocket area, it just seems like a worn out sprocket is far fetched?

The oil pump seal on the old front case shows no signs of damage or wear. So I’m wondering if anyone has actually seen a sprocket wear like this?
 
Is it possible that all this is caused by the use of a stub shaft in place of the eliminated balance shaft?

Problems with the stub shaft type of oil pump are a thing, yes. It's why some people like to use a "race shaft" type setup there instead of a stubby. Yours seems extreme though, for how quick it happened (if that's what happened).
Helical oil pump gears vs straight gears, that's another thing. (More problems with helical)
Aftermarket parts there usually bad, OEM more good.
Take a look at post #15 about deburring the gears, in this thread:
https://www.dsmtuners.com/threads/gsc-power-division-race-balance-shaft.465352/#post-153282988

As far as the stub shaft, when Tim Zimmer posted just a few weeks ago that his engine ran fine for 3X,XXX miles and XX dyno pulls at XXXX hp etc etc etc, I asked him 2 questions. What kind of oil are you using, and are you using the stub shaft type pump and if so how many oil pumps did you go through during that time?
He said he's using an OEM stub shaft type and he's never had to change it. Starting from post #32 here:

When my engine was built in 2015 I asked Lucas English if they would use a race shaft type of oil pump in it. He said no. He said they would refuse to build the engine if I insisted on a race shaft. Which surprised me because ER likes most of the GSC stuff and GSC makes or did make a race shaft.
I don't like the overhung load aspect of the stub shaft (like a cantilever) but apparently it can work!

BTW my oil pressures are also pretty high. Pretty similar to what DSMPT described in post #60. He and I are using 20w-50 oil though which raises pressure, everything else being equal.
 
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Problems with the stub shaft type of oil pump are a thing, yes. It's why some people like to use a "race shaft" type setup there instead of a stubby. Yours seems extreme though, for how quick it happened (if that's what happened).
Helical oil pump gears vs straight gears, that's another thing. (More problems with helical)
Aftermarket parts there usually bad, OEM more good.
Take a look at post #15 about deburring the gears, in this thread:
https://www.dsmtuners.com/threads/gsc-power-division-race-balance-shaft.465352/#post-153282988

As far as the stub shaft, when Tim Zimmer posted just a few weeks ago that his engine ran fine for 3X,XXX miles and XX dyno pulls at XXXX hp etc etc etc, I asked him 2 questions. What kind of oil are you using, and are you using the stub shaft type pump and if so how many oil pumps did you go through during that time?
He said he's using an OEM stub shaft type and he's never had to change it. Starting from post #32 here:

When my engine was built in 2015 I asked Lucas English if they would use a race shaft type of oil pump in it. He said no. He said they would refuse to build the engine if I insisted on a race shaft. Which surprised me because ER likes most of the GSC stuff and GSC makes or did make a race shaft.
I don't like the overhung load aspect of the stub shaft (like a cantilever) but apparently it can work!

BTW my oil pressures are also pretty high. Pretty similar to what DSMPT described in post #60. He and I are using 20w-50 oil though which raises pressure, everything else being equal.
Thank you for the replay and info from the other post, this definitely gives me more confidence in the stub shaft since I am nowhere near the HP range of Tim's car probably.

I just hope replacing the oil pump sprocket actually fixes this mess i've have been in with this car for so long.

The fact that my previous oil pump was smoke and I only had 500 miles on it with no hard racing or anything must mean I installed the belt too tight....

the story with my car is a very long one,.. I assembled the engine 18 years ago and just left it sitting, I never primed it or started it, I just occasionally rotated the motor after pouring oil down the cylinders. At that time I am very certain I installed the belt very tight which may explain the ruined oil pump on my previous case, this may also be a reason the sprocket is worn out??
 
Is it possible that all this is caused by the use of a stub shaft in place of the eliminated balance shaft?
The stub shaft has nothing directly to do with the leak from that seal. The drive gear shaft, yes. But what the seal is actually sealing is the sprocket, not the shaft. If your stub shaft is the cause of this issue, then you have issue with your oil pump, you would probably have to replace everything, the front case, the drive gear, the driven gear and the stub shaft.

The oil pump drive gear shaft was totally worn out and I needed to use a hammer to remove the drive gear shaft out of the case. The shaft wore terrible grooves into the case.
This case, yes. It would possibly cause a leak from the seal.

The front case only had 500 miles on it (this was a new case as well). Could this all be because the timing belt was too tight?
Like I have already mentioned above. Possibly yes. You have to inspect the drive gear shaft and the sleeve on the front case to know that.

I’m certain now the leak is coming from the oil pump sprocket area, it just seems like a worn out sprocket is far fetched?
You have to inspect the condition of the sprocket where contacts the seal and if the drive gear shaft is sitting straight and no abnormal play. If the drive gear shaft has a lot of play, that causes the leak.
If you believe the leak is occurring that area, should inspect below.
1. The seal isn't seated/installed properly or damaged.
2. The front case drive gear shaft sleeve or/and oil pump drive gear is out of spec (deform)/damaged.
3. The sprocket where it contacts with the seal is out of spec (deform) or damaged.
4. Abnormal oil pressure.
5. Drive gear shaft drain hole is clogged. (Unlikely)

I installed the belt very tight which may explain the ruined oil pump on my previous case, this may also be a reason the sprocket is worn out??
Usually No. What you would damage first from too much tension on timing belt is the drive gear shaft and the front case sleeve. As I have already told you, this would make the sleeve oval and it would damage inside of the case under the gear cover. And finally the drive gear shaft and the sprocket wouldn't sit straight and cause some space between the seal and the sprocket. This cause the leak from the seal.

Check the pics in the link below (Post #54), this is what normally happens when you run the engine with too much tension on timing belt.

Didn't you ever hit the pistons and valves really badly before and reusing the same sprocket? In this case, the sprocket may be cracked or deformed.
 
The stub shaft has nothing directly to do with the leak from that seal. The drive gear shaft, yes. But what the seal is actually sealing is the sprocket, not the shaft. If your stub shaft is the cause of this issue, then you have issue with your oil pump, you would probably have to replace everything, the front case, the drive gear, the driven gear and the stub shaft.


This case, yes. It would possibly cause a leak from the seal.


Like I have already mentioned above. Possibly yes. You have to inspect the drive gear shaft and the sleeve on the front case to know that.


You have to inspect the condition of the sprocket where contacts the seal and if the drive gear shaft is sitting straight and no abnormal play. If the drive gear shaft has a lot of play, that causes the leak.
If you believe the leak is occurring that area, should inspect below.
1. The seal isn't seated/installed properly or damaged.
2. The front case drive gear shaft sleeve or/and oil pump drive gear is out of spec (deform)/damaged.
3. The sprocket where it contacts with the seal is out of spec (deform) or damaged.
4. Abnormal oil pressure.
5. Drive gear shaft drain hole is clogged. (Unlikely)


Usually No. What you would damage first from too much tension on timing belt is the drive gear shaft and the front case sleeve. As I have already told you, this would make the sleeve oval and it would damage inside of the case under the gear cover. And finally the drive gear shaft and the sprocket wouldn't sit straight and cause some space between the seal and the sprocket. This cause the leak from the seal.

Check the pics in the link below (Post #54), this is what normally happens when you run the engine with too much tension on timing belt.

Didn't you ever hit the pistons and valves really badly before and reusing the same sprocket? In this case, the sprocket may be cracked or deformed.
The pistons never hit the valves on this motor..
I understand what you’re are saying about the worn out drive gear shaft and case bore, but the case is brand new with 150miles in it and I ensures the belt was not overtightened. However, there is one more thing I forgot to mention because I thought it was irrelevant. The alternator is relocated using the BS Jay Racing relaxation kit. I say BS because the tension rod is weak and almost over extends to the point where the rod runs out of thread… well the rod that bolts to the “joints” on the kit are worn and my alternator produces a nasty vibration @ 2500 RPM that teleports throughout the entire motor. I noticed one day the the vibration is induced on the crank shaft dampener and timing belt… well imagine the timing belt vibrating as the alternator freaks out at 2500 RPM. Could this be destroying my oil pump and causing this leak you think?
 
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