Have a warning for people that use 100% methanol. I have found out the hard way and confirmed with people in the know. Make sure you have no oil in the combustion chamber while spraying. Methanol will detonate on oil instantly and it doesn't matter what afr you are running.

I can't confirm whether this would happen while running mix meth/water or even denatured.

I confirmed it after personally talking to Chris Neidemire(Justin Humphries crew chief).

Piston 1
Piston 2
Piston 3
Piston 4

I am still confirming why my built motor was having so much blow by. Still haven't ruled out piston malfunction/mis-manufacture. I have feeler gauged piston to wall clearance at .026.

Ivan

 

how did you know there was a problem? what were the signs?

 

+1 ^

 

Only signs I had were excessive blow by, I would constantly pop my dipstick tube out under boost. I also had a knocking noise coming from the bottom end. It didn't sound like a bearing.

Best guess is oil came out the valve cover and sucked through the turbo into the intake track.

I pulled the head and was welcomed to that. All 4 CP pistons have the same marks on the intake reliefs. 2 worse then the other 2. So I had a few people check around and one tuner picked it out as a meth problem, without even being told I had meth.

I also confirmed it when I talked to Chris on Saturday. He said they dropped a valve guide in the race car and it damaged that piston.

Two things I'm going to do, once I get the engine back together. Put in a propper catch can setup and install the krank vent check valves. I'm also not going to run injection until I can confirm I have the oil under control and at that it will probably be water or some mix.

 

do you have an oil pressure gauge? were the readings steady? and what catch can are you running?

 

No oil pressure gauge, but this thread isn't for figuring my problem. That will be figured once I pull the pistons and measure. The engine had a nasty harmonic at 6100 rpm, which could be the excessive piston play. I know my problem was more the likely boost blowing by the rings forcing oil into the intake track. Now that I know what I know, I will have a better catch can/oil control/pcv setup.

This is to let people know of the meth/oil problem. Which seems is unknown, except to people that have dealt with 100% methanol cars. Just wanted to get a warning out there, incase people start popping motors from detonation and can't figure why.

 

This is not good...Is there a check besides pulling the head???
I had my dip stick pop out once..(last year)

 

I wouldn't worry if it did it once. Mine was doing it everytime I hit boost and blowing lots of oil out at the time. The dipstick blowing out is a result of my piston size problem.

Your car wouldn't run or run well if it broke part of the piston. No need to guess you would know for sure.

 

The dip stick thing seems to be pretty common when pushing decent power. Mine kept popping out when i installed my 3065 and i thought it was blow by for sure until i ran a leak down test and everything checked out. Zip tie worked for me but im still not sure of alternative way to fix the problem.

Back on topic, this seems like a pretty serious matter, i know a couple guys that run straight meth, do you think the problem could have been blowby in the first place? Did you ever run a compression test when your motor was built?

 

Best thing I have found to "fix" the problem is the krank vent valves(dejon tool). Which I have now.

Agreed, I didn't know about it and seems like most wouldn't. Best thing I can guess is oil was forced out the valve cover and made it's way into the intake track. Excessive blow by would accelerate that, also a weak/leaky pcv valve.

The biggest thing is oil could come through the intake track, from a valve seal/guide or in reality a few other things.

I guess the fair warning should be, if you plan to run straight meth make sure to have a proper oil control system in place and keep track of plugs and engine health.

Most people's(dipstick popping) problem is more then likely the pcv valve not doing it's job.

 

Good call on the vent valves. dejon tool is the shiat. Thanks for the warning and all the info, im planing on running straight meth but am still deciding if its the best rout for me.

 

NP, I still like the kick of it. Though it will take me a little while to want to run it again. The motor was really fresh and I can't afford yet another rebuild after this one. So race gas for me.

 

Umm are you checking the line venting the valve cover to the intake?? Thats how oil is getting into your intake track.

 

I ru straight meth but haven't had any issues with my dipstick popping out. My plugs have never looked funny from oil, but I have noticed that my oil pressure gauge starts to fluctuate under boost. Guess I'll have to look into these vent valves.

 

This is known, the motor had maybe 20 minutes of boost on it (not all at one time). What isn't known is the actual size of the pistons and if they had a defect, causing the excessive blow by, which in turn cause so much oil to be passed in such a little time.

Can't say if they would help. Though from what I've seen the stock pcv valve stinks. They were on my list of things to get for a long time and they quickly made it near the top.