1G Brand new and.... Kaboom.

[YawnY]

First drive this spring to do a base tune, had driven the car in the fall to get gas before winter then parked. Ran car in the garage afew times and had no issues. Set idle, timing, base afr. Go for a quick drive.
Did a small pull, hit 7 psi and then she let go.
Brand new gates belt, brand new tensioner. Less than 3 km on it.

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[99dsmer4g63]

The gear looks brand new, I guess it's just the picture. No clue why the pump locked up. I'm stumped.

You think you may have over tightened the timing belt causing the oil pump to fail prematurely?

-Daniel

 

[YawnY]

You think you may have over tightened the timing belt causing the oil pump to fail prematurely?

-Daniel

I don't think so. I followed the manual, and have done these belts before. If it was way to tight then the tensioner would have been bottomed out when I did the belt.

 

[curt-s]

The front case and pump housing could have been manufactured incorrectly.
Who here in the city are you taking the block and head to for cleaning and who is doing the machine work?

 

[YawnY]

The front case and pump housing could have been manufactured incorrectly.
Who here in the city are you taking the block and head to for cleaning and who is doing the machine work?

Joe's Machine decked my head. Great guys, very old school. Not sure if they're still open. Last I talked to them they were closing and possibly moving.

I have a spare head and set of valves, the valve seat wasn't damaged, so I'll swap in some valves and lap em. The oil was clean, and nothing was in the filter. So I'm not to worried. I'll check the mains to make sure they're clean and clear.

 

[curt-s]

I'm quite surprised nothing was in the filter. That pump and case is trashed..

 

[1990TSIAWDTALON]

How did the threads on the end of the shaft get all buggered up?

 

[YawnY]

How did the threads on the end of the shaft get all buggered up?

Was stuck in the pump housing. Used a hammer to get it out.

 

[1990TSIAWDTALON]

Gotcha. I figured that there was a problem but wanted to ask. Hell of a mess! Crossing fingers for you on the bearings and all of the oil passages.

 

[dwb]

It's pretty obvious that the seized oil pump is what caused the timing belt failure. The question that needs answered, was the oil pump part of cascading failure or was it the initiator?
It looks like the large gear was rubbing only on one side of the pump housing which would indicate a lateral force on the sprocket. That would put stress on the shaft and bore and potentially cause them to seize together. Where did this lateral force come from? The only thing I can think of would be the timing belt but you mentioned it was tensioned properly. Does your rear idler pulley spin freely?

 

[Justin DuBois]

If this was mine, I'd pull the engine and start looking for damage. For sure you will want to pull the pan, inspect the mains, and the rods. You have to ask youself - given what you have seen so far - what path to repair is required.

 

[danl]

Did the pump get starved of oil?

 

[DSMPT]

Typical damage on both belt and oil pump from too much tension. (The oil pump drive gear/shaft wasn't sitting straight)

 

[enriquez2000]

Looks like a bad flux capacitor or ejecto seato malfunction

 

[Dericsh]

Looks like a bad flux capacitor or ejecto seato malfunction

Proper ejecto seato can be critical!

 

[curt-s]

@YawnY You back up and running this year?

Also noticed the two stubby shaft pics are different. Yes I know this is old news
One set is helical gear and the better looking ones are straight. Which did you have installed when it let go?
Im just curious because I literally put together my pump moments ago
Can't get that sprocket nut torqued and I don't want to clamp the stub shaft to do it.

 

[jed344]

I will add when deleting balance shafts we many many years ago started using the 90 straight cut oil pump gears in all the DSM cases. I have a oil pump here I took off my motor likely 7 years ago that was deleted but kept the helical and in less then 1k miles it TRASHED the gears. This was on a motor that did 788whp on Whalenspeed's dyno. With much lower power use cases I have seen the helical not be a issue when deleted though.

That looks like to me as well like over tension damage. We always after doing it come back later and turn motor over again by hand and make sure we can put the pin back in.

Crazy enough this pump still made great oil pressure, was not noisy, and showed no shavings noticeable in the oil. Only caught it when i was refreshing the motor.

 

[YawnY]

@YawnY You back up and running this year?

Also noticed the two stubby shaft pics are different. Yes I know this is old news
One set is helical gear and the better looking ones are straight. Which did you have installed when it let go?
Im just curious because I literally put together my pump moments ago
Can't get that sprocket nut torqued and I don't want to clamp the stub shaft to do it.

I'm back up and running. Car is running strong, and haven't had any issues so far (fingers crossed). I had straight cut gears and the oem stub shaft. Used an oil pump off a spare engine, fixed the head and cleaned everything as best I could. Already ran 5 tanks of gas through the car, hoping to get some dyno time before winter.
I'm pretty sure I installed everything then torqued the stub shaft while holding the oil pump drive with a wrench.

 

[curt-s]

I will add when deleting balance shafts we many many years ago started using the 90 straight cut oil pump gears in all the DSM cases. I have a oil pump here I took off my motor likely 7 years ago that was deleted but kept the helical and in less then 1k miles it TRASHED the gears. This was on a motor that did 788whp on Whalenspeed's dyno. With much lower power use cases I have seen the helical not be a issue when deleted though.

That looks like to me as well like over tension damage. We always after doing it come back later and turn motor over again by hand and make sure we can put the pin back in.

Crazy enough this pump still made great oil pressure, was not noisy, and showed no shavings noticeable in the oil. Only caught it when i was refreshing the motor.

I had about 30k km on a helical geared Mellings case and pump. While it had more wear on the housing than my current straight cut, it still survived with great pressure and no shavings. The balance shaft doesn't have a thrust surface to prevent lateral walk, it's held in place by oil pressure on the surface of the gearset in the pump, no?

So I would think, BS or not, the same ability for the helical gears to provide lateral force exists. Without BS, your pressure in that area should be higher as well but perhaps it's that same higher oil pressure forcing the gear horizontally.

Anyhoo, @YawnY, I need to see your car some day.. haven't been out since I'm still building.

 

[jed344]

I had about 30k km on a helical geared Mellings case and pump. While it had more wear on the housing than my current straight cut, it still survived with great pressure and no shavings. The balance shaft doesn't have a thrust surface to prevent lateral walk, it's held in place by oil pressure on the surface of the gearset in the pump, no?

So I would think, BS or not, the same ability for the helical gears to provide lateral force exists. Without BS, your pressure in that area should be higher as well but perhaps it's that same higher oil pressure forcing the gear horizontally.

Anyhoo, @YawnY, I need to see your car some day.. haven't been out since I'm still building.

Had to do with the gears not being supported correctly as I recall with a stub shaft and helical gears. The stub shaft looked perfect. The case and cover where torn up badly from the gears walked apart under load and driving into the case and cover. Helical gears provide quite operation but under load want to move away from each other. Straight cut gears are noisy but do no walk apart from each other.

 

[curt-s]

But that's what I'm saying, they want to walk whether there's a balance shaft or not, it's the oil film that prevents (or should) them from walking through the case. Oil pressure around the stub shaft body, assuming it's a proper stub, should prevent perpendicular movement l. However, I do see that having a long balance shaft also providing more journal surface support along its length in multiple places would serve to prevent "wobble" more with a helical set.

 

[YawnY]

I had about 30k km on a helical geared Mellings case and pump. While it had more wear on the housing than my current straight cut, it still survived with great pressure and no shavings. The balance shaft doesn't have a thrust surface to prevent lateral walk, it's held in place by oil pressure on the surface of the gearset in the pump, no?
So I would think, bs or not, the same ability for the helical gears to provide lateral force exists. Without bs, your pressure in that area should be higher as well.. but perhaps it's that same higher oil pressure forcing the gear horizontally.

Anyhoo, @YawnY, I need to see your car some day.. haven't been out since I'm still building.

There's not much to look at since the car sat in the sun uncovered since 2006, most of the paint has faded. I rescued the car before it went to the junk yard. It looks rough but goes pretty good. Two of my friends have 1g's and we all trade parts and knowledge to help keep them alive.

 

[curt-s]

There's not much to look at since the car sat in the sun uncovered since 2006, most of the paint has faded. I rescued the car before it went to the junk yard. It looks rough but goes pretty good. Two of my friends have 1g's and we all trade parts and knowledge to help keep them alive.

Indeed, you grabbed some stuff off me a couple years back.
It's patina, not faded
If I can get my two guys out in their 1gs as well we could have a bit of a presence. A few more 1gs popped up since I sold mine, there used to only be a couple left in the city. Good to hear there's even more, I almost never see any now.

 

[jed344]

But that's what I'm saying, they want to walk whether there's a balance shaft or not, it's the oil film that prevents (or should) them from walking through the case. Oil pressure around the stub shaft body, assuming it's a proper stub, should prevent perpendicular movement l. However, I do see that having a long balance shaft also providing more journal surface support along its length in multiple places would serve to prevent "wobble" more with a helical set.

Correct. People smarter then me likely could explain it better. I just have first hand tried both multiple times and it ends up this way from personal experience. When you catch it early on enough the case/cover are worn in a 180 degree circle. Not a full 360 so that would mean the gears are tilting as walking apart.

 

[YawnY]

Indeed, you grabbed some stuff off me a couple years back.
It's patina, not faded
If I can get my two guys out in their 1gs as well we could have a bit of a presence. A few more 1gs popped up since I sold mine, there used to only be a couple left in the city. Good to hear there's even more, I almost never see any now.

I'm definitely using the parts I got off you! I have the fmic on but haven't gotten around to installing the rear shocks.
Would be nice to get a DSM meet going but us 3 all work for the rail road and have weird shifts.

 

[YawnY]

Indeed, you grabbed some stuff off me a couple years back.
It's patina, not faded
If I can get my two guys out in their 1gs as well we could have a bit of a presence. A few more 1gs popped up since I sold mine, there used to only be a couple left in the city. Good to hear there's even more, I almost never see any now.

Hey do you have a spare 2g maf I could try for 5 min? I fired up my car yesterday and she was reading real lean at idle. Don't want to buy a new maf just to find out the ecu is bad.