Well the short story is, I had a forged eng built and it has been burning oil about every time I drove it. I would go through a drive-thru and it would look like the car was on fire. Changed oil and it got much better, not burning as much oil as before. Car still had great power. I ended up going on a trip to the beach and checked oil the next day and was about 3/4 of qt low. The trip was 150 miles one way. Got home and it was about 3/4 of qt low again. Talked to builder and he said we would do a compression test and leak down. Here are the results from that:
Compression Leak down
1-202. 2%
2-210 2%
3-212 2%
4-230. 2%
5-240. 2%
6-212. 2%
7-200. 2%
8-210. 3%


We opted to pull eng since it was smoking. Here are the pictures of the engine... curious as to what the eng gurus thought had happened? Car has always had great oil pressure like 45-50 psi hot idle. The engine has 1,028 miles since build. Builder thinks it is from the cylinders being washed with fuel. I am trying see what others are thinking. I do know every time I kick it, it would smoke like a diesel.

 

You have to be getting a ton of blow by in that to use that much oil. Looks like the walls of the holes has a ton of more than 1,k on it. Plus was the block honed to what pistons you are using in the motor.

May be the pic,s but looks like alot of just slick spots down in the walls also. Plus what does the plugs look like that you pulled from each hole. Then what about the color and if wet on the valve's after you pulled the heads off the block. Robert

 

Leak down is done with the piston at TDC. If the bore is good there, you get good numbers.

Those bores look odd to me. There are areas where it looks like the rings never touch.

Was it bored? Then honed to size with a torque plate?

When you say smokes like a diesel, you mean black smoke?

If it's really washing the bores with fuel, I'd expect horrible mileage and the oil to smell like gas along with fouled plugs.

 

Probably not

 

A friend had one that ate oil and smoked like a train. It turned out to be a problem with a head. A hole in the intake runner causing it to draw in oil under vacuum. Didn't find it until after the shortblock was rebuilt, then replaced a shortblock and was still doing it. 3 shops worked on it. Tons of money spent and then I fixed in my garage.

 

Definitely not honed with a torque plate... You can see the "shadows" on the skirt side of the walls. Doesn't even look like the skirt to wall clearance was set right... (Piston to cylinder wall)

Its crazy how high that cranking psi was on some of the cylinders....I hope it's not a boost motor with 230-240 cranking psi... Not to mention the 20% variance in cranking psi amongst the cyls..

Basically start over and have the builder do it right this time, or find another builder.

 

Ditto! The clean shadow looking location on the bores look just about like where the hone doesn't touch at first when torqued down with a plate. Lots of stud force pulling in that location. Hard to say for sure, but something isn't happy.

 

The fuel mileage from the beach trip was 16.3 mpg! That is not good. the car only made 700 rwhp. I did smell the oil and it smelled of gas. The plugs were br7ef's gaped at 22.



YES it was torque plate honed! The piston diameter is 3.8995 and the bore was 3.905, that means the clearance was .0055 per my build sheet. When I say it smokes like a diesel I mean, it smokes black and clouds out the road. I have pulled oil sample and it was elevated in fuel %. The plugs were all black and 3 of them were oil fouled bad. thanks for all the help

 

I would double check that.

Measure the cylinders with a bore gauge for out-of-round with a torque plate installed then without the torque plates installed.

The cylinders will be out-of-round when you take a reading without the torque plates if it was properly honed.

 

Ok will have them measured tomorrow, but I do know it was torque plate honed. I was shown the pictures of the eng while it was being done. This is by far not the first lsx engine built by the builder. I am just having a hard time seeing that it has not been torque plate honed. I will try and find the pictures of it on the machine. He is telling me it is from too much fuel and deluting the oil down. The oil in the engine was very thin and smelled of fuel. Thanks for the responses.

 

Who did the tune? (if you can say)

 

Was the tune clean from the start of the new engine or at least decent? You don't want to be way off on fueling the first start of the new shortblock and wash the rings down.

EDIT I think I was half sleeping when I wrote the above

 

?? I had them install the file for the new id850 injectors before start up. I know total seal warrantied the ap gapless rings and they opted to try a different set of rings at no cost. Only thing that was different from the tune before was the cam and 60# injectors for the most part. (New engine). I know there is some talk of the ap gapless rings but that doesn't look like it was the reason for the scaring on pistons, and cylinders. Thanks for all the responses, just trying to find out what happened to not have to deal with it again.

 

Again from the pic,s say it was what Joe is tell you to do and check out. No way 1,k miles will have that much wear on pistons and C/walls.

 

Talked to builder again today, he said that the block was torque plate honed piston to cylinder. The machine shop that does his work is one of the few in the area with the proper tools for the lsx engines. Actually the person that built the motor also has helped build Mark Carlyle's engine. I know it was built correct. The builder said he has seen similar issues in other lsx engines. Thanks again for all the help so far.

 

I don't want to sound like I am belaboring it, but those piston/rings are not evenly contacting the cylinder walls.

The pattern of wear seems to line up with the head bolts.


BTW, I was also told that my motor (2 rebuilds ago) was honed with torque plates.

Look at my cylinder walls just after one weekend of racing. When AES checked my cylinder walls they confirmed out-of-round. I seen it in person.

BTW, PM responded.




.

 

The cylinders do not look to good, but also take a look at the rocker bolt holes to the intake port. Some port jobs will leave the bottom of that hole open and oil will suck threw the threads pretty easily. If so you have to use sealant on the bolts.

Sorry if this was covered, I didn't read every response.

 

Yes I would agree with you on this, but the heads are stock. They have never been touched other than springs. I will go over the heads and check for cracks in the intake area though. All the marks are on the thrust side if the cylinder also. The builder is standing behind it and taking very good care of me with the issue. The tuner is also helping me out. We are going to check bore this weekend with and with out torque plates on them for peace of mind for me.

 

When sitting in Erik Koenig's shop one day, he shared with me one reason he doesn't like aluminum blocks with stock sleeves for big power. He showed me stock and rebuild motors with mileage on them and shined his flashlight down the bores to better expose these high and low spots that exist inherently. "You knock them down and they come back in other places". It seems to me that what you're possibly looking at on the cylinder walls is simply a result of what we're stuck with. Pistons with short skirts and the major and minor thrust areas are going to get rubbed down by the piston skirts.
Considering how many motors I've seen with this shadowing that you've got and how few of them were smoking before being disassembled, I would consider Doug's comment. I would also consider the fact that you're saying it's smoking black. That's not oil. Fuel in the oil? Well if you're hosing down the cylinders with too much fuel, the rings aren't going to stop it all. Depending on how rich you're actually running, it could affect your ring sealing performance.
400 grit hone 20-25° angle with a plateau hone afterwards. Torque plate using YOUR studs/bolts and torqued to YOUR specs if you're using reusable fasteners.
All of your clues add up to the truth of the story. Fouled, black plugs indicates if you're closed loop that you could have dead 02's and the PCM trying to compensate for false 02 readings. When shows a false lean condition and it doesn't get results, it keeps pushing more and more fuel into the engine until the trims are maxed out, essentially a runaway freight train. If your 02's are in fact working, when you foul plugs and misfire cylinders from it, you're pumping added oxygen into the exhaust, creating a false lean condition and again creating the runaway freight train effect.

 

Bret I am with you on this, that is why I ask him what the plugs was looking at from each hole. But then again Bret remember this motor was just done plus has less or just 1,k miles on it. It has to be getting some hel! of fuel down the holes plus who ever did the work on the block and honing had to do one bad job on it. Plus the OP had to have this car at WOT the full time. Robert