low compression on built motor..

[plow420]

Hi everyone this is my 3rd built motor that has failed me.... first two spun number 4 rod bearing..

Well anyways the shortblock was built buy a very reputable company and it was broken in right. The controlled aggression way, lots of oil changes. It was tuned on e85 and the max boost it has ran is 18lbs..

Anyways one day i noticed quite a bit of oil coming from the breather, so i did a compression test and here are the results... from left to right.. 150,140,115,140 that is dry... wet it goes up to 190 and 150 in the low cyl...

I also did a leak down test to confirm that it was the rings.... i could hear air coming from dipstick and crankcase

What do you think i should do? drive the piss out of it till the cyl totally gives out, because i've been pretty nice to it so far. I haven't had a running car in the summer since my car was stock 4 years ago..

I don't think they are going to stand behind their work. Their warranty basically covers nothing the way it is. And how could i prove that the ring clearances were bad.. their is no way..

 

[97gsxIA]

PM the name of the company if you wish and maybe I can help. I wouldnt go throwin their name around publically though just in case

 

[plow420]

PM the name of the company if you wish and maybe I can help. I wouldnt go throwin their name around publically though just in case

pm sent

 

[BogusSVO]

How many miles on the rebuild?

 

[plow420]

How many miles on the rebuild?

I guess i forgot to add that.. Its a little over 2,800 miles.

 

[allwheelTSI]

Just keep in mind, that wet testing can cause compression numbers to be very erratic unless you know exactly what you are doing. So it very well still may be in the head depending on what you came up with. Dumping oil into the plug holes usually gets trapped sitting in the dish on top of the piston, and if you use enough, it spills over the piston into the ring lands that you need wet for the test to work. Problem is, the oil pooled on top of the piston does not compress and therefore gives you an artificial bump in static compression.

The proper way to do it, or well.. The way I like to do it. is to take a syringe, the kind without the nedle attachment. So you have a nipple to attach a length of hose. I then use that to slide in the plug hole and while the tubing usually already has a natuaral curvature which is conducive to squirting the oil in sparing ammounts while rotating the syringe a bit for every few drops. This ensures it runs down onto the ring lands evenly and gives you accurate numbers.

Anybody that has pulled a head after a "normal wet test" knows what I'm talking about, and how much oil is actually sitting in the piston dish, which I personally think is more than enough to inflate 10-20psi on a gauge.

Also, as far as proving their build was inferior, they aren't gonna pay if they don't want to, thats just one of those things. But as far as showing proof, you can show pistons with unsealed rings and discern them easily from a working piston which had good sealing rings. You just look at the sides of the piston and you'll be able to see where its changing color pasts the first ring and has black soot down past that first ring. This indicates the lack of seal showing combustion forces were pushing the mixture past your rings.

 

[plow420]

Just keep in mind, that wet testing can cause compression numbers to be very erratic unless you know exactly what you are doing. So it very well still may be in the head depending on what you came up with. Dumping oil into the plug holes usually gets trapped sitting in the dish on top of the piston, and if you use enough, it spills over the piston into the ring lands that you need wet for the test to work. Problem is, the oil pooled on top of the piston does not compress and therefore gives you an artificial bump in static compression.

The proper way to do it, or well.. The way I like to do it. is to take a syringe, the kind without the nedle attachment. So you have a nipple to attach a length of hose. I then use that to slide in the plug hole and while the tubing usually already has a natuaral curvature which is conducive to squirting the oil in sparing ammounts while rotating the syringe a bit for every few drops. This ensures it runs down onto the ring lands evenly and gives you accurate numbers.

Anybody that has pulled a head after a "normal wet test" knows what I'm talking about, and how much oil is actually sitting in the piston dish, which I personally think is more than enough to inflate 10-20psi on a gauge.

Also, as far as proving their build was inferior, they aren't gonna pay if they don't want to, thats just one of those things. But as far as showing proof, you can show pistons with unsealed rings and discern them easily from a working piston which had good sealing rings. You just look at the sides of the piston and you'll be able to see where its changing color pasts the first ring and has black soot down past that first ring. This indicates the lack of seal showing combustion forces were pushing the mixture past your rings.

I know that the pistons are wiseco 1400hd 9.0:1 so there is still a dish. I used a cap full of oil in each cylinder and it could have pooled up, but a 40psi increase is quite a bit for that i think.

I also shined a flashlight down the sparkplug holes and noticed that the really low cyl had a lot of black carbon looking crap all over it and the other three were cleaner. But not as clean as i've seen with motors that have only ran e85 like mine.

I went to harbor freight and bought a cylinder leak tester. And when i hooked it up you could hear air rushing out of the oil dipstick and the oil fill on the head. Nothing was coming from the intake side or the exhaust

 

[travs92vr4]

I would drive it till it gives you driveability issues. That is considerably less compression in the one cylinder. Do you notice any vibrations or other issues? If they won't cover the motor with the warranty, and it was my car, I would drive it till it let go or till i got a misfire or a vibration issue. I wouldn't pull the motor prematurely. Just my .02 cents.

 

[plow420]

I would drive it till it gives you driveability issues. That is considerably less compression in the one cylinder. Do you notice any vibrations or other issues? If they won't cover the motor with the warranty, and it was my car, I would drive it till it let go or till i got a misfire or a vibration issue. I wouldn't pull the motor prematurely. Just my .02 cents.

The only issue that i had was i have a 6bolt block with a 2g head and using a 6 bolt cam angle sensor and a 95 eprom ecu and 96 wire harness i got a random multiple misfire code if i would cruse after about 500-600 miles . I was told to disable the cyl misfire check for that because of my 6bolt swap. I did that and the car runs just fine. There is no noticeable vibration, I have the idle turned up to 1000rpms to help with the cams, poly mounts, and lightweight flywheel. Helps for dive ability.

Does anyone think i should pull the head and look at pistons? What would i see if the rings didn't seal?

 

[travs92vr4]

The only issue that i had was i have a 6bolt block with a 2g head and using a 6 bolt cam angle sensor and a 95 eprom ecu and 96 wire harness i got a random multiple misfire code if i would cruse after about 500-600 miles . I was told to disable the cyl misfire check for that because of my 6bolt swap. I did that and the car runs just fine. There is no noticeable vibration, I have the idle turned up to 1000rpms to help with the cams, poly mounts, and lightweight flywheel. Helps for dive ability.

Does anyone think i should pull the head and look at pistons? What would i see if the rings didn't seal?

Ok, well the misfire code is not a big deal. What does your spark plugs look like? Do a plug read. Is the tune good on it?

I would not pull the head unless you want to sink more money in it. And if thats the case, you might as well just pull the motor instead of just pulling the head.

If there is no noticeable vibration, and it runs good and doesn't smoke, I would not pull the head or the engine. The compression test might have been compromised some how...

 

[Boomdeeze]

Could you PM me the shop that built it as it must be one located here in MN.

ANd if it runs good and they won't warranty their work, I would just run it until it gets bad. Summers here and I know the feeling of wanting to drive it so i would if it were me.

 

[plow420]

Ok, well the misfire code is not a big deal. What does your spark plugs look like? Do a plug read. Is the tune good on it?

I would not pull the head unless you want to sink more money in it. And if thats the case, you might as well just pull the motor instead of just pulling the head.

If there is no noticeable vibration, and it runs good and doesn't smoke, I would not pull the head or the engine. The compression test might have been compromised some how...

The low cyl is really dark and has oil on it. The other plugs are not as clean as they should be. The tune might be a little rich up top like 11.8 according to wb. This exact motor has not been tuned. My other two build were tuned at db performance and this build is exactly the same minus the turbo now. All did was change some settings on the maf and everything was good.

I can take a picture of the plugs if that would help.

I dont think that test was compromised because i did it myself first. Than i brought it to a shop and did another test there with the same results.

I can do all the work myself and pull the head, its not hard i've pulled this motor at least 8 times by now.

Could you PM me the shop that built it as it must be one located here in MN.

ANd if it runs good and they won't warranty their work, I would just run it until it gets bad. Summers here and I know the feeling of wanting to drive it so i would if it were me.

You are correct it is in MN, it is probably the most well know shop in MN

They want me to take the shortblock to them so they can take it apart and inspect it. But they document all of their builds, so i'm sure they will just show me papers that the rings were gapped at whatever they were, and ask me to pay for the dissemble.

All i want is a reliable dsm. I've not cheaped out on any aspect of this motor and it still failed me.

I paid $2,646 for the shortblock without the cost of pistons,rods and block....

I expect quality work for that much money.

 

[bastarddsm]

personally, at 2800mi, I'd have it apart and see whats going on. I'd be inspecting the head first before I pull the short block apart. Fill the ports with mineral spritis, and see if any of the valves leak. A drip here or there isn't a big deal, but a stream is bad.

If it all checks out there, I'd be pulling pistons to see whats going on.

Obviously, if you've had 3 built motors go bad, then something is wrong. Either the clearances were way off, or the finish is shit, ect..

 

[travs92vr4]

The low cyl is really dark and has oil on it. The other plugs are not as clean as they should be. The tune might be a little rich up top like 11.8 according to wb. This exact motor has not been tuned. My other two build were tuned at db performance and this build is exactly the same minus the turbo now. All did was change some settings on the maf and everything was good.

I can take a picture of the plugs if that would help.

I dont think that test was compromised because i did it myself first. Than i brought it to a shop and did another test there with the same results.

I can do all the work myself and pull the head, its not hard i've pulled this motor at least 8 times by now.



You are correct it is in MN, it is probably the most well know shop in MN

They want me to take the shortblock to them so they can take it apart and inspect it. But they document all of their builds, so i'm sure they will just show me papers that the rings were gapped at whatever they were, and ask me to pay for the dissemble.

All i want is a reliable dsm. I've not cheaped out on any aspect of this motor and it still failed me.

I paid $2,646 for the shortblock without the cost of pistons,rods and block....

I expect quality work for that much money.

Well if this is the 3rd motor from the same shop...I think this is a hint hint scenario. No matter how much money you throw at them, they still can't build a good engine. If you don't mind the car being down, let them warranty it out. And ask them if they charge for tearing it down...

 

[plow420]

personally, at 2800mi, I'd have it apart and see whats going on. I'd be inspecting the head first before I pull the short block apart. Fill the ports with mineral spritis, and see if any of the valves leak. A drip here or there isn't a big deal, but a stream is bad.

If it all checks out there, I'd be pulling pistons to see whats going on.

Obviously, if you've had 3 built motors go bad, then something is wrong. Either the clearances were way off, or the finish is shit, ect..

The head was redone, It has new seals and new oem valves with a 3 angle valve job, and light port work done to it. It has also only been resurfaced once.

The first two built motors that went bad were because oil contamination i'm sure.

Well if this is the 3rd motor from the same shop...I think this is a hint hint scenario. No matter how much money you throw at them, they still can't build a good engine. If you don't mind the car being down, let them warranty it out. And ask them if they charge for tearing it down...

This the the first motor from this company, the other one i built myself and the one after that i had the help of a known engine builder locally here help me. And all they assembled was the shortblock so thats all the want from me. I cant imagine how much they would have charged me to put the whole motor in the car.

All i want is to drive my car.... even just one summer would be amazing... one track day.. anything is better than having all this money stuck into something you cant enjoy.

 

[bastarddsm]

Liquid test the valves, and see if thats the issue. If it is the shortblock you might get away with a ball hone and a set of rings.

 

[plow420]

Liquid test the valves, and see if thats the issue. If it is the shortblock you might get away with a ball hone and a set of rings.

Do you still think it could be the valves even after i did a leak down test and i could hear lots of air coming from the crankcase and dipstick tube?

I'm pretty sure it is the shortblock. Could the cyl walls could be messed up from the pistons since the they are letting oil by?

Is there any chance the pistons are messed up?

Or would a ball and hone work, or would i need a overbore going from .020 to .030 or .040?

Thanks everyone for their input!!!

 

[bastarddsm]

Do you still think it could be the valves even after i did a leak down test and i could hear lots of air coming from the crankcase and dipstick tube?

I'm pretty sure it is the shortblock. Could the cyl walls could be messed up from the pistons since the they are letting oil by?

Is there any chance the pistons are messed up?

Or would a ball and hone work, or would i need a overbore going from .020 to .030 or .040?

Thanks everyone for their input!!!

It's worth a shot, pretty easy to test that...

Whats the story on the pistons? New? brand?

if you take it apart, make sure you keep the rings and pistons all together, and remember what cylinder they were from.

 

[plow420]

It's worth a shot, pretty easy to test that...

Whats the story on the pistons? New? brand?

if you take it apart, make sure you keep the rings and pistons all together, and remember what cylinder they were from.

The pistons were bought new by me on my first build. Every time i put new rings on them. This last time i put new rod pins and locks in them including new rings. They are wiseco 1400 hd 9.0:1 pistons. The pistons looked new and checked out every time.

And i don't really want to take it apart. I paid a shop to assemble my motor and now it failed. There was nothing i could have done to prevent it. I did everything right. I feel like they should hone the block and re ring the pistons and put new bearings in if it was something that they did wrong.

 

[1gslotsi]

I would pull the motor and head take it and let them warranty it and as before check about charge for tear down and inspection that's why you payer what you payer to have it assembled to begin with and the biggest thing is to stay courteous because that will take you a long way with companies and they should be understanding if it will be down king buy a used shortblock and throw it in and beat on it as hard as possible enjoy the car good luck keep us posted

 

[plow420]

I would pull the motor and head take it and let them warranty it and as before check about charge for tear down and inspection that's why you payer what you payer to have it assembled to begin with and the biggest thing is to stay courteous because that will take you a long way with companies and they should be understanding if it will be down king buy a used shortblock and throw it in and beat on it as hard as possible enjoy the car good luck keep us posted

I have been really courteous so far. Its been really hard to do because i want to tell them how i fell about it all. But i know everyone makes mistakes and if they will admit it and rectify it is another story.

I really want to get a g4cs aka 4g64 6bolt to spool my turbo, currently a fp3065. Does anyone know how much power a stock g4cs will take before it will break? I use e85 for fuel and use a 2g head.

I just want to enjoy my car. It seems like I'm burning hundred dollar bills for no reason what so ever.

And I will keep everyone posted what happens with my situation.

 

[travs92vr4]

Sounds like a mess, and a personal choice to drive the car till something goes wrong, or take it back to them and see if they will warranty it. Cars are money pits! No way around it... They will drain the wallet as long as you have the need for speed.

 

[plow420]

Sounds like a mess, and a personal choice to drive the car till something goes wrong, or take it back to them and see if they will warranty it. Cars are money pits! No way around it... They will drain the wallet as long as you have the need for speed.

Fast enough is never Fast enough, that is for sure, But if they don't warranty it will drive it until the low cyl goes out and never do business with them again, and tell everyone my story and strongly not recommend them to everyone i know and talk to.

I knew what i was getting into.. but never did i think i would go threw a motor a year without even putting 3k miles on them.

 

[bryanwheat]

I would just pull it apart and re-ring it myself. I wouldn't want them re-assembling another possible junk engine.

 

[plow420]

I would just pull it apart and re-ring it myself. I wouldn't want them re-assembling another possible junk engine.

Everything that would need to be done is, New rings, new bearings and possibly a hone? what if the cross hatching looks good?

Could the pistons be messed up from the rings not setting?