Im at a loss, ridiculous blow-by please help

[RunawayValet]

Okay, 1G stock motor/new rebuild dr650 car on e85 running 28psi. Was tuning the car after about 1500 miles (dont ask) and started to over heat in 3rd and 4th after high boost pulls. When I checked the coolant I noticed some oil in the coolant, but no coolant in oil. I flushed and decided to keep an eye on it. Shortly after doing some more pulls I started getting some crazy blow-by, blew the hose between valve covers out, blew the camshaft seal caps out. So I bought a catch can, and routed the valve covers to the catch can. No dice, it just pressurized the catch can and blew oil out the top of that. Finally did a compression test and the results were, front bank all ~170, rear 30, 60,and 170ish. So I think head gasket, probly from overheating. I replaced the rear head gasket with MLS, I made sure to inspect the cylinder walls to look for scoring from a possible bad ring, looked good. I replace the head and put it all back together. Now the same blow by, there is actually exhaust coming out of the valve cover vents now. And compression numbers are exactly the same. I know rings are a possibility but the walls looked great. Is there anything I am missing?

Thanks for any help you can offer.

[NOMIEZVR4]

Hmm...the fact that you have exhaust pulsating through your catch can indicates that there still may be a breach in the combustion chamber..now thru what means is what you have to figure out. Did you have the block/heads checked for flatness? You sure you didn't install the HG upside down or backwards? I would grab a coolant system pressure tester and pressurize the system to look for any visible leaks...start from there and lets see where that leads us.

Also while you are at it, pressure test the car and see how much blow by you still have. Recently was working on a 2.4 evo that was just built, it has CRAZY blowby--when pressure testing, so much pressure came out of the oil cap that unless one person wasn't fully pressing down all their bodyweight on the oilcap, we weren't able to pressurize it because of such intense blow by--and thats with a catchcan he had installed too with some really big AN lines.

[anyonebutme]

leakdown test

[TwIzTeD_3kGt]

Describe your "new rebuild". Sounds like the problem will lie somewhere within that description.

[familyMAN]

If you blew a headgasket, you now have a warped head or block or both. Sounds like it is time to pull the engine and get block and heads resurfaced. Also look for busted piston/rings.

[RunawayValet]

I had the head decked for this new gasket, which I didn't do the first time. He took off 4/1000. However I did not have the block checked.. New rebuild meaning all stock parts with new bearings, rings (which I checked with feeler gauges for appropriate gaps) new valve stem seals and re-seated valves. It didnt need rebuilt I just did it because I had it apart.

There is A LOT of oil in the boost pipes, before and after the IC, on both sides, in the bubble, in the throttle body.
When the car runs if I take the oil cap off it looks like the exhaust pipe.

[RunawayValet]

FamilyMAN after doing the headgasket and yielding the same compression results, that most likely was not the issue. Everything leans towards broken rings, but in 2 cylinders?? With no signs of wall damage? I thought maybe cracked block..

[familyMAN]

These blocks rarely crack (if ever). At the risk of sounding like banned member steve, "busted ringlands":D. As suggested already, do a leakdown test to see if it's valve or ring related. Also pressurize your coolant system to see if you breached the head gasket again.

[RunawayValet]

My leakdown tester is a POS, however when the head was off I made sure to check all the valve seats and they were fine. I will pressurize the coolant system and post back, thanks guys.

[anyonebutme]

you don't even need a leakdown tester, just hook the compression tester adaptor to air compressor and put pressure in the cylinder and see where it comes out

[KeithMac]

Given the low compression and exhaust gasses in the crankcase/ breathers it can only really be ring failure?. Especially due to the extent of blow by gasses..

[Roybatty]

How did you mod your pcv system? With compression that unbalanced I would think blow-by is the least of your issues atm...but is all interrelated.. could be ringlands...head can put oil in intake...

Revel in your time

[J. Fast]

you don't even need a leakdown tester, just hook the compression tester adaptor to air compressor and put pressure in the cylinder and see where it comes out ^^this^^ put the cylinders in top dead center and bottom dead center and fill!

[donniekak]

Probably burned some rings. E85 melts pistons and rings before it detonates and breaks the piston.

[RunawayValet]

Well guys I pulled the pan and pulled the head and this what I found..

http://i417.photobucket.com/albums/pp254/roguewarrior8/image.jpg (http://s417.photobucket.com/user/roguewarrior8/media/image.jpg.html)

Broken ring lands on 2 pistons. Probly from lack of oiling from a rich mixture. I'll pull the rest and inspect.

[LeRoyDL]

bummer deal, block still has cross honing markings no strait lines?

[donniekak]

Ringlands break from detonation.

[RunawayValet]

Block still has beautiful honing marks. There are some straight lines but they were there before assembly, I cant catch them with my fingernail. I had the machine shop look at them and they decided a hone would suffice.

Donnie, the most knock I ever logged was 8 counts and that was once and on gasoline. After that I had none. Running a 10-10.5/1 afr on the gas scale with e85. Im not convinced it was detonation. If it was how do I tell for next time if I can't log it??

Ill get rings, bearings, and HGs and probably end up getting forged pistons in the stock size. I don't know I am uhhh not happy.

[donniekak]

If you we're running 10:1 on e85 you probably had rich knock(misfires). Also ethanol is sensitive to preignition. I run non projected 8 heat range plugs for anything over 25psi.

[anyonebutme]

Also....check your ring end gap......breaking the 2nd land doesn't sound like the typical knock induced damage to me but I'm no expert. Seen plenty of top lands go bye bye from knock. I was told bad things happen to ring lands when the rinds butt.

[TwIzTeD_3kGt]

Block still has beautiful honing marks. There are some straight lines but they were there before assembly, I cant catch them with my fingernail. I had the machine shop look at them and they decided a hone would suffice.

Donnie, the most knock I ever logged was 8 counts and that was once and on gasoline. After that I had none. Running a 10-10.5/1 afr on the gas scale with e85. Im not convinced it was detonation. If it was how do I tell for next time if I can't log it??
Ill get rings, bearings, and HGs and probably end up getting forged pistons in the stock size. I don't know I am uhhh not happy.

E85 detonation does not get picked up by our knock sensor. Someone correct me if I'm wrong, but torque output is how you determine whether or not you're knocking on E85. Advance timing until torque no longer increases, then back it off a bit for safety.

[J. Fast]

Block still has beautiful honing marks. There are some straight lines but they were there before assembly, I cant catch them with my fingernail. I had the machine shop look at them and they decided a hone would suffice.

Donnie, the most knock I ever logged was 8 counts and that was once and on gasoline. After that I had none. Running a 10-10.5/1 afr on the gas scale with e85. Im not convinced it was detonation. If it was how do I tell for next time if I can't log it??

Ill get rings, bearings, and HGs and probably end up getting forged pistons in the stock size. I don't know I am uhhh not happy.

Next will be bent rods. You need lighter and stronger rods. If I may suggest Pauter Rods with the upgraded oil chamfer option. What manufacturer and style of bearing are you going with?

[RealMcCoy]

rings (which I checked with feeler gauges for appropriate gaps)

What I'm not reading here, is: "I ground the rings to an appropriate gap for a DR650 car at 28 psi that I'm going to overheat and try to stick the rings..."

I don't even know what you set them at, but if you didn't grind on them, they were too tight....

Where's Steve68 when you need him....

[familyMAN]

These blocks rarely crack (if ever). At the risk of sounding like banned member steve, "busted ringlands":D. As suggested already, do a leakdown test to see if it's valve or ring related. Also pressurize your coolant system to see if you breached the head gasket again.


What I'm not reading here, is: "I ground the rings to an appropriate gap for a DR650 car at 28 psi that I'm going to overheat and try to stick the rings..."

I don't even know what you set them at, but if you didn't grind on them, they were too tight....

Where's Steve68 when you need him....

I was channeling Steve68 in my earlier post:D

[RunawayValet]

Okay I made a chart for the ring gaps but I cannot find the damn thing, they were all within the spec that was given to me by the ring company, well within spec, THAT is why I didn't grind them. They are stock pistons/rods/crank because well there was nothing wrong with them when I rebuilt I just wanted a fresh motor, and I was under the assumption that a stock bottom end is supposed to hold the power of dr650s, I talked with Ray about it before I purchased them. It would be nice, and safe, to have forged rods/pistons but it is not needed for this build.

I chose E85 because I wanted to be able to run high boost without running race gas, and I can get e85 very very cheap.

For the guy who asked what bearing company, I used clevite and will continue to use clevite.

[RunawayValet]

I didn't know our knock sensors could not pick up knock from e85... Maybe the source was detonation in this case. It definitely fell off at high rpm, but I thought it was from running rich and crappy stock cams.

[KeithMac]

I've never seen genuine knock on e85 with our sensors either, I think if you get to that point it's already far too advanced!.

When I used it I didn't go mad with the timing and just enjoyed running more boost safely rather than hitting the ragged edge.