0 Oil pressure after warm up with Autometer Gauge

[HondaGuywithDSM]

Well I have searched and all the threads I have found end with the OP saying they would get a aftermarket gauge and check again.

I have a rebuilt 6 bolt block, evo 9 pistons with 1g rods and 7 bolt head. I also have the balance shafts removed and 3G lifters. When I first start the car it has perfect oil pressure at 11.5 at idle. As I accelerate it goes up as it should but once the car is warmed up and I am at idle the after market gauges reads 0 PSI. This makes me very nervous it's keeping me from driving the car My gauge is Autometer electric gauge and the sender is remotely mounted.

Any help I would greatly appreciate it.

 

[My1GLaser]

Your oil pressure should be a LOT higher than that when you first crank it up. I'm pretty sure mine is at least 50psi. It's about 15-20psi at idle when warm. Autometer electronic gauge with a remote oil pressure sender line run to the OFH. It's actually on a Tee fitting to my turbo to monitor pressure and I have a restrictor in the line right off the OFH. I'm sure the pressure my engine sees is even higher than that.

What oil are you running?
Where is your pressure source?
Did you use new bearings to block off the oil passages to the balance shafts or at least rotate the old bearings 90*?
Check for leaks to your gauge and to the sender!!!

 

[HondaGuywithDSM]

Sorry I wasn't clear oil pressure shows about 30 psi when first turned on. After it warms up a bit and then it goes down to 11.5. Then if I drive it after a few miles is when idles shows 0. I am running 5w 30 and the pressure source is where the factory gauge was plugged in at the OFH. I used new bearings to block off the oil passages

 

[DSM1G90]

WHY are you using 5w/30 oil ...

Minimum weight is 10w/30 for DSM motors since they don't have that tight of clearance for anything thinner..

Almost would say that the connecting rod bearings are tired letting oil slide by them when the oil thins up when hot, which will cause the difference in pressure reading between cold and hot, but with you saying a new rebuilt was done recently, which also one could ask the question if the motor was broken in properly and using dino oils instead of jumping straight to synth oils which will prevent the proper break-in period.

 

[My1GLaser]

What does it read at WOT at like 5 or 6k rpms?

When it drop to 11.5 and the car is "warm" what are you using to judge if it's up to operating temp? The gauge on the dash is in the "normal" range on my car long before my car reaches operating temp according to DSMlink and my electronic fan control.

What were your bearing clearances when the motor was built? Maybe you need to switch to something like 15w40 to get your pressure right. I'd say that 30 psi cold is still too low, assuming your gauge is accurate, but the 5w30 probably accounts for some of that.

Was your OFH ever ported? Maybe it was over-ported and it's always bleeding pressure...

 

[HondaGuywithDSM]

I am using 5w 30 because it gets cold here. It is conventional oil. The engine was just recently rebuilt. It has 39.2 miles on it so it's still breaking in. I got new ACL rod bearings installed.

I forgot to add I still have the oil squinters.

I just went out side and turned on the car. Sorry correction at first start up oil psi is 79 then slowly goes down. After 11 min the stock temp gauge is right below halfway that's how I determined the engine was hot and the oil pressure was at 11.5. I waited another 6 minutes and it dropped further to between 10 and 10.5 at that point I shut the car off. I am guess if I let it idles even further then eventually it would be at 0

bearing clearances ? I got STD bearing sizes. OFH is completely stock. No porting I don't know what my pressure is at during WOT since the engine hasn't been broken in I've been taking it easy. If you guys think it will help I will change my oil to 15w 40 tomorrow and report back.

 

[JusMX141]

I am using 5w 30 because it gets cold here.

Not cold enough.

Here's a recent thread you may want to read: http://www.dsmtuners.com/forums/newbie-forum/470123-thinnest-oil-4g63-fuel-efficiency.html

bearing clearances ? I got STD bearing sizes.

That's reassuring.

So I take it you didn't plastigage anything upon assembling the engine to verify that all of the oil tolerances were correct? I've seen where machinists cut just one rod or main journal on a crank before....

 

[chaggard27]

The crank was actually inspected at a machine shop an all journals were measured and then the crank was polished. All checked good so therefore std bearings were used without the worry of having to measure it all.

 

[95blackGsTurbo]

Did you replace the stock oil pump or check the gears for play. That is the biggest problem I see if people just look at the gears and housing, think they look ok and reinstall it and then they have oil pressure problems.

http://www.dsmtuners.com/forums/newbie-forum/385202-oil-pump-tolerance-check.html

 

[HondaGuywithDSM]

well I changed the oil over to 15w 40 today and took it for a 10 mile test drive. Now the oil pressure is at 1 to 2 psi at idle versus the 0 before. I wanted to take this approach first because it was cheap and easy. chaggard27 is my mechanic is going to source another 6 bolt oil pump and we'll see then. Hopefully its sooner or later but regardless I will let you guys know. Thanks for your help and if anyone has any more input please let me know.

 

[DSM1G90]

std bearings were used without the worry of having to measure it all

Too much assumption here. Still a safe practice to double check everything before calling it good.

39.2 miles on it so it's still breaking in

HOPE you're using dino oil instead of synth, for that motor will NEVER get broken in using synths.

Plus, a cheap straight weight 30 or 40w dino oil is a good oil for break-in and you change it :50 miles, 100 miles, 300 miles, 500 miles so the rings can get seated in along with the similar items.

-DSM

 

[95blackGsTurbo]

well I changed the oil over to 15w 40 today and took it for a 10 mile test drive. Now the oil pressure is at 1 to 2 psi at idle versus the 0 before. I wanted to take this approach first because it was cheap and easy. chaggard27 is my mechanic is going to source another 6 bolt oil pump and we'll see then. Hopefully its sooner or later but regardless I will let you guys know. Thanks for your help and if anyone has any more input please let me know.

This is a band-aid not a fix. Thicker oil just masks the fact that there is a larger problem. As far as oil pumps go when rebuilding, you don't "source" one. You buy a new one when needed. It is way to important of a component in the system to be using a used part on. I would be very leery of a mechanic using used oil pumps, even ones that spec out good.

 

[HondaGuywithDSM]

Since the rebuild the car has been running only conventional oil ... Dino oil

I will be purchasing a brand new oil pump

Thanks for the break-in advice, I guess since I just changed it at 39.2 miles it will count towards my 50 miles change. I will change it again back down to 10w 30 when the new oil pump goes on and then after another 100 change it again and so on

As of now though the miles are going up because the car will not be driven until this issue is solved. I can't afford to rebuild it again.

 

[91fwdnightmare]

considering the b.s.e kit id pull the oil pump off and make sure that the b.s (balance shaft) bearings have been rotated properly, so that the oiling hole is not just open.
is it a turbo'd block? if it is it could be a loose or broken oil squirter check those things before you condem the rod/main bearing size! if its none of the above put a new oil pump on it.

 

[HondaGuywithDSM]

well I have ordered a new oil pump the one that's on the car is a used one so I felt it would be best to get a new one. When the new oil pump goes on we'll check to make sure the BSE bearings are correct.

Yes it is a turbo block, I purchased new oil squirters for the build.

 

[HondaGuywithDSM]

Well after replacing the oil pump the car continued to do almost the same thing except that it would idle after fully warm at 2 psi. I went down to summit racing because it's local and picked up a $20 mechanical oil pressure gauge and it shows 15 psi at idle. I suspect it's a little high because of the oil, I will be going back to 10w30 but it's way better than 0 psi. I don't regret having the oil pump changed because the car does run better. So just wanted to say thanks to everybody and that this issue has been resolved.