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2ndGenGuy
01-25-2008, 01:30 PM
I was wondering if a lean condition in the motor or in a cylinder could cause excess blowby to buildup in the crankcase. I noticed today that one of my spark plug was never tightened down (I'm a dumbass!), and was wondering if that could cause a lean condition in the motor, causing excess blowby...

2oodoor
01-26-2008, 03:37 AM
yes once it has burned a hole in your piston :Owned:
you still having those issues? did you change the head from another type engine? this sounds familiar, too much compression because of not enough CC in the head.. may need relief type pistons? I dunno , I will go back and read your build thread.

2oodoor
01-26-2008, 12:02 PM
I dont know just how important the orifice is but looking at your block it does have a place for it. Oil jet orifice, rear side of head about the size of a head bolt hole, yours is right beside a head bolt hole in the middle of the block between 3 & 4. Something else would be oil pressure relief valve, do you have a guage? is it reading excessivly high.. just thoughts.

2ndGenGuy
01-27-2008, 12:24 AM
No I don't have a gauge, and it makes me wicked nervous. But I'm not really having the problem anymore since I made a makeshift catchcan. But I was wondering if that was possibly a contributing factor.... The head is the head for that motor, thought from another engine since mine was cracked. But I'll crack that valvecover and check out those oil jets or pressure relieve valve or what I can find about them. Thanks!

2ndGenGuy
02-04-2008, 04:23 PM
So I finally got the engine broken in. I decided to see how she would go today, and I found that under load the engine is a bit weak, and continues to blow oil out of the valve cover. At engine speeds below 3000RPM it doesn't do blow oil out, so I haven't seen that for the last couple weeks since I've been babying it...

I also noticed that there were two sets of marks on the cam gear, about 12-15 degrees apart. I may have the cam timing set a little too advanced. Going to correct that tomorrow morning and see if that fixes things.

2oodoor
02-05-2008, 11:20 AM
windage tray? baffles in the valve cover?
is it smoking out the back?

Ichiban
02-05-2008, 05:56 PM
Sounds like you might have broken/upside down piston rings. We built an AMC 360 with moly rings once and they absolutely refused to seat. Might wanna do a leakdown and compression test.

lostforawhile
02-05-2008, 07:09 PM
Sounds like you might have broken/upside down piston rings. We built an AMC 360 with moly rings once and they absolutely refused to seat. Might wanna do a leakdown and compression test.yea what kind of oil did you use? never use any kind of synthetic or semi synthetic when breaking in an engine. it reduces friction so much that the rings never seat. how long have you been driving it? even a newly rebuilt motor will sometime smoke for a while until the rings have seated. when the motor was rebuilt,were the cylinders honed to remove glazing,and put the proper cross hatch pattern on them? i belive they still make break in oil too,they used to it helps the rings to actually seat.

lostforawhile
02-05-2008, 07:23 PM
here read this article http://www.mototuneusa.com/break_in_secrets.htm

Ichiban
02-05-2008, 07:34 PM
yea what kind of oil did you use? never use any kind of synthetic or semi synthetic when breaking in an engine. it reduces friction so much that the rings never seat. how long have you been driving it? even a newly rebuilt motor will sometime smoke for a while until the rings have seated. when the motor was rebuilt,were the cylinders honed to remove glazing,and put the proper cross hatch pattern on them? i belive they still make break in oil too,they used to it helps the rings to actually seat.

Was that question for me or John? That engine was pulled apart and the rings replaced, as with any rebuild the cylinders were honed and break in was done with a petroleum based oil with no energy conserving additives. We replaced with iron pre-gapped rings and honed again lightly. After 8-10 short duration full throttle loading events, most of the previous blowby observed was gone. After 5-6 years, that engine is still running. We also replaced the crankshaft and bearings, due to the engine running out of oil during break in with the old rings. That's how much oil it was expelling/burning. The last main and both rear rod bearings were toasted. The rings and crank re+re was actually done with the block in the vehicle, a 1984 CJ-7.

The first build of my 22R died due to ring related issues. After the first 2 or 3 months, the engine developed a piston slap noise when cold, which went away when the engine warmed up. After a few more months, it was knocking bad, from around #4. While I was moving and hauling shit around, #4 let go and produced so much blowby that the truck was undriveable. Compression was around 190-185-188-65 if I remember correctly. The compression ring on #4 had actually rolled out of it's groove and buried itself sideways in 2 layers into the thrust side of the piston. The first symptom on both failures was a lot of blowby.

2ndGenGuy
02-05-2008, 08:17 PM
Sounds like you might have broken/upside down piston rings. We built an AMC 360 with moly rings once and they absolutely refused to seat. Might wanna do a leakdown and compression test.

Yeah, definitely going to do the leakdown and compression tests this weekend. The car seems to be sort of lacking in power as well, but I was assuming it was more a carb tuning issue... Hopefully that checks out okay. I assumed that if there were broken rings or something up with them, I might be getting some smoke in the exhaust.

I did initially have synthetic in it, but it was only for about 24 miles, and I took it out after finding out that was a bad thing. I was hoping that hasn't done any permanent damage, but I figure it couldn't if it hasn't even allowed the rings to wear. I figured once I put regular oil in, it would be like starting from square one.

Could mis-adjusted valve lash cause this problem too? The machinist who assembled the head said it was already set, but I was a dumbass not to double check that. Wish I wasn't busy as hell this week with work. I need some time to check everything out and get it set up proper-like.

Also, I pulled another dumbass move in my hurry to get it running. Instead of using the proper timing belt tensioner bolts I used some that fit... I also didn't have the tensioner spring. Well, long story short one of the bolts backed out and the belt got all floppy and the car started running bad. Could the pressure be exhaust going past a bad valve seal from a bent valve stem?

I'm mainly wondering what all could cause blow by like that, so I can go over everything and double check it before I get to tearing the engine back apart. :( Valve timing, ignition timing, mixture, anything I can check to narrow things down?


here read this article http://www.mototuneusa.com/break_in_secrets.htm

Hmm... I dunno if that's something I'm comfortable with. Like the article says over and over "Why does Honda recommend a procedure that won't seat the rings?" And then he doesn't answer it...

I think that after building 19,038,413,904,890,384,293,048,390 engines, Honda, Yamaha, etc, etc, might have a reason for doing it the way they do... Running a brand new motor hard just doesn't seem like a good idea... My machinists, and friend who has built sub-11 second engines, recommend the traditional method. Lots of new cars even have a break in mode in the ECU that won't let the car go above a certain RPM or vehicle speed until the first 500 miles are completed.

I will keep this article in mind for sure, as it was an interesting read, but I doubt I'll go with the "beat on it" method to break in the engine until I hear from a few more people on that one...


windage tray? baffles in the valve cover?
is it smoking out the back?

Do you mean that tray in the oil pan that keeps oil from splashing about? That was fine last time I looked at it. Also the valve cover baffles are okay, I blew into the vent on the valve cover, and I can feel the air come out the oil cap hole. Also, no smoking out the back. My catch can is capturing plenty of mayo...

Thanks for the help everybody. It's really appreciated. :wave:

2ndGenGuy
02-05-2008, 08:31 PM
yea what kind of oil did you use? never use any kind of synthetic or semi synthetic when breaking in an engine. it reduces friction so much that the rings never seat. how long have you been driving it? even a newly rebuilt motor will sometime smoke for a while until the rings have seated. when the motor was rebuilt,were the cylinders honed to remove glazing,and put the proper cross hatch pattern on them? i belive they still make break in oil too,they used to it helps the rings to actually seat.

My machinist did hone the cylinders for me... And a few other people looked at it and said that it looked good. So I'll assume I'm safe on that one. They were bored out a bit, since they had some weird wear patterns. I've got 500 miles on it now, and at idle, the blow by isn't excessive, just under load. So maybe the rings still haven't seated yet thanks to my nice dose of synthetic. Did the 500 mile oil change, and have fresh, non-synthetic in it still. Never did get any smoking out the tailpipe though.

2oodoor
02-06-2008, 04:28 AM
Yeah, definitely going to do the leakdown and compression tests this weekend. The car seems to be sort of lacking in power as well, but I was assuming it was more a carb tuning issue... Hopefully that checks out okay. I assumed that if there were broken rings or something up with them, I might be getting some smoke in the exhaust.

IDo you mean that tray in the oil pan that keeps oil from splashing about? That was fine last time I looked at it. Also the valve cover baffles are okay, I blew into the vent on the valve cover, and I can feel the air come out the oil cap hole. Also, no smoking out the back. My catch can is capturing plenty of mayo... Thanks for the help everybody. It's really appreciated. :wave:

Mayo? you picking up water ?

Seems like if it was a ring problem it would be smoking like bitch ??:gun:

Yep those Yamaha HO type engines are toast if anything in them does not clear anyway so you may as well wind her up green, if something is going to break anyway it is going to be a do over.:eatarrow:

lostforawhile
02-06-2008, 01:24 PM
Mayo? you picking up water ?

Seems like if it was a ring problem it would be smoking like bitch ??:gun:

Yep those Yamaha HO type engines are toast if anything in them does not clear anyway so you may as well wind her up green, if something is going to break anyway it is going to be a do over.:eatarrow:
he's picking up the normal water which is part of combustion,normally without the catch can it would be pulled through the pcv system and burned in the engine. this shows a point to of how important that system is. your normal combustion byproducts contain water vapor,and if it wasn't for the pcv system keeping that air moving,it would condense in your engine and become sludge.

2ndGenGuy
02-06-2008, 03:01 PM
he's picking up the normal water which is part of combustion,normally without the catch can it would be pulled through the pcv system and burned in the engine. this shows a point to of how important that system is. your normal combustion byproducts contain water vapor,and if it wasn't for the pcv system keeping that air moving,it would condense in your engine and become sludge.

Yeah, after seeing that nasty stuff in the bottle, I'm glad it's not going back into my engine for reburn!

lostforawhile
02-06-2008, 04:28 PM
Yeah, after seeing that nasty stuff in the bottle, I'm glad it's not going back into my engine for reburn!
well the water vapor goes out the tailpipe it doesn't hurt anything.

2oodoor
02-07-2008, 04:50 AM
sounds like pvc system needs doo over :o)>

2ndGenGuy
02-07-2008, 11:19 AM
Yeah, I'm thinking maybe the PCV can I made isn't sealing anymore. Maybe not enough vacuum. Making a new catch can this weekend to hopefully solve the problem. And going over all the timing and everything... Damn work taking up all my time this week. Only had time to check the oil, which BTW seems like the level is higher than when I filled it.

When I checked the level on the dipstick after the oil change, it was right in the middle of the two lines. Now it's damn near the top line, AFTER blowing out oil. Maybe I just overfilled it, but I don't see how, since the manual says 3.7 quarts, and I only put 3.5 quarts in. Maybe I shouldn't touch cars anymore! :(

Ichiban
02-07-2008, 06:07 PM
Maybe you have a headgasket sealing problem. That could explain the white goo, and the increase in oil level. I'm curious if you have an inch of coolant in the bottom of your oil pan. Also, combustion pressure could be leaking into the crankcase.

After throwing out every imaginable theory, I still recommend a compression/leakdown test, as well as a coolant system pressure test.

Another thought I had about the white goo in the catch can is this: Normal operation heats the oil enough to fume off water that shows up due to inevitable amounts of blowby. Possibly this water is condensing in the catch can (the only "out route" for the water vapor in the crankcase) as it's remote to the engine and nowhere near as hot.

2ndGenGuy
02-09-2008, 11:40 PM
No water in the oil pan. When I changed it last weekend, it was as clear as the day I put it in the engine. The coolant level hasn't dropped a bit yet either.

Did some tightening up of things today though. Found that the cam timing is quite allright. I double checked it, and it all looks good. The ignition timing was way off, not sure how that happened, but I think it's related to a BAD vaccum leak from my canister that was ghetto-ified in there. Also, the carb adapter plates were leaking pretty bad too. Some butane in a can told the story VERY well.

I fabbed up a new catch can, and made sure this one wouldn't leak. Did the vacuum test with my tongue, and found the new one is not leaky. :D Also going over my adapter plates and re-torquing and adding a couple dabs of sealant where metal is thin and has great leakage potential (around the areas where the first plate bolts down).

Hopefully this will take care of everything, and my oil blowing out the seals was merely caused by the lack of vacuum from all the damn leaks... I'll find out tomorrow. Nice to get all that little crap taken care of finally, been such a long week with no time to work on the car at all.

2oodoor
02-10-2008, 04:32 AM
^^^ your tongue? what are ya... tasting soup up there? burnt your tongue cells up drinking scorching hot coffee.. lol j/k

Watch out for those studs on the carb, they can grab and start turning when you tighten up the carb nuts, then they are just pushing the plates apart. I used a gasket as a template and made a thick gasket out of and aluminum foil box., on one of those gaskets<< has to be the box with metalic type surface on the outside...works like a champ.

2ndGenGuy
02-10-2008, 10:12 PM
Yeah, the tongue test... you know like when you put your tongue on your straw and it gets stuck when you're drinking a milkshake? If you tongue doesn't come out of the vacuum hose fitting, it's nicely sealed. :D

Actually, found that you were right, roodoo. There was a nasty vacuum leak because I tightened those studs down too far. Not only that, but the countersunk screws in the bottom base plate weren't flush with the top of the adapter. They were sticking up a bit. Had to use a drill just to take the lip off of the top and the screws sunk down nicely.

Took care of ALL the vacuum leaks (there were lots). The car runs so fucking magnificent now. It's got tons of power, and will probably run circles around my 2g now.

But after tightening everything up. Checking timing, and everything else, it still blows oil at high RPMS. I've come to the conclusion that I fucked it up by starting with synthetic, and my rings aren't seating.

I'm going to give it a few good hard runs as advised by that site that Lost sent me and see what happens. I know they suggest doing it sooner, but it's too late for that, and I need the rings to seat. Worse case scenario, I rehone and rering the cylinders. Not a huge deal I suppose...

2oodoor
02-11-2008, 04:40 AM
Yeah, the tongue test... you know like when you put your tongue on your straw and it gets stuck when you're drinking a milkshake? If you tongue doesn't come out of the vacuum hose fitting, it's nicely sealed. :D

Actually, found that you were right, roodoo. There was a nasty vacuum leak because I tightened those studs down too far. Not only that, but the countersunk screws in the bottom base plate weren't flush with the top of the adapter. They were sticking up a bit. Had to use a drill just to take the lip off of the top and the screws sunk down nicely.

Took care of ALL the vacuum leaks (there were lots). The car runs so fucking magnificent now. It's got tons of power, and will probably run circles around my 2g now.

But after tightening everything up. Checking timing, and everything else, it still blows oil at high RPMS. I've come to the conclusion that I fucked it up by starting with synthetic, and my rings aren't seating.

I'm going to give it a few good hard runs as advised by that site that Lost sent me and see what happens. I know they suggest doing it sooner, but it's too late for that, and I need the rings to seat. Worse case scenario, I rehone and rering the cylinders. Not a huge deal I suppose...

I still don't get why no smoke? any ash on the plugs?
A good break -in road with short but steep grades works well, that way you can power on, then decel, power on and decel.. or just a long streight road with a gradual downgrade.
I hope you get that part fixed without any majors.

Ichiban
02-12-2008, 07:46 PM
I still don't get why no smoke? any ash on the plugs?
A good break -in road with short but steep grades works well, that way you can power on, then decel, power on and decel.. or just a long streight road with a gradual downgrade.
I hope you get that part fixed without any majors.

It's my experience that you don't get much smoke on a compression sealing problem like this. Keep in mind that the bottom compression ring is actually not a compression ring, but an oil scraper. Just because the top ring is allowing pressure past it does not mean that the bottom ring is letting oil back up to be burnt, and perhaps all that blowby is pushing the oil off of the cylinder walls back into the crankcase. Even with the top ring on #4 in pieces on my 22R, it only burnt oil when it was pushed out the breather into the intake. Other than that, there was no indication of anything wrong, besides poor compression and noise when cold.

I also read (and lost) an interesting article on ring seating. Basically it states that short, hard loading cycles are preferable to long gentle ones because of oil coking, which will glaze the cylinder walls and prevent proper break in. The short loading cycles force the rings against the walls to wear them in, and the off throttle stage allows cooling to occur, thus avoiding high heat, coking and glaze. Far as I know, you want to do the WOT loading cycles as soon as possible after the engine is running, as the fresh honing pattern holds a lot of oil, and "going easy" on the engine will probably glaze it right up.

I seem to remember seeing that article on H-T and I believe Accordtheory posted it here on 3geez.

2ndGenGuy
02-12-2008, 11:39 PM
With low compression, would I not be lacking in some power? The car is incredibly powerful (relatively), but of course I only have the 310,000mile 2g to compare it to. I think it would easily take a newer Civic though. :D

Just picked up a compression tester this evening. I'll test it in the morning and post my results...

2ndGenGuy
02-13-2008, 12:16 PM
Well compression is as follows

185 - 180 - 180 - 185

Seems good to me, eh? I think the rings are seated? So WTF. Maybe I just need to get vacuum to vent the case when I'm at WOT. Maybe get a valve that can split off the vacuum so when I romp on it, it diverts airflow up into the air cleaner, and pulls crankcase pressure out that way...

2oodoor
02-13-2008, 12:34 PM
Leakdown tests?

2ndGenGuy
02-13-2008, 02:02 PM
Need to get a leakdown tester. :eatarrow:

Ichiban
02-13-2008, 05:16 PM
Need to get a leakdown tester. :eatarrow:

Me and guy made one by splicing in a T fitting between the compression tester gauge and the hose. It has a valve and an air fitting, so you can air up the cylinder, close the valve and watch the pressure drop.

2ndGenGuy
02-13-2008, 06:38 PM
Me and guy made one by splicing in a T fitting between the compression tester gauge and the hose. It has a valve and an air fitting, so you can air up the cylinder, close the valve and watch the pressure drop.

What about cranking the cylinder to TDC which should bring the gauge up to 180psi, right? Then if the pressure drops, will that mean I've got leakage? Or do I need more pressure than that?

2oodoor
02-14-2008, 04:34 AM
What about cranking the cylinder to TDC which should bring the gauge up to 180psi, right? Then if the pressure drops, will that mean I've got leakage? Or do I need more pressure than that?

think about what you just said:)

that would be like measuring a fart (psi) , you only have that one moment for each event, you need to be able to measure regulated sustaining pressure, (ouch)

the guage has a check, you need external pressure:cheers:

2ndGenGuy
02-14-2008, 03:26 PM
think about what you just said:)

that would be like measuring a fart (psi) , you only have that one moment for each event, you need to be able to measure regulated sustaining pressure, (ouch)

the guage has a check, you need external pressure:cheers:

I've always wondered what the pressure of a fart was. :toilet: I'll get my hands on a leakdown tester. :)

lostforawhile
02-14-2008, 04:32 PM
I've always wondered what the pressure of a fart was. :toilet: I'll get my hands on a leakdown tester. :)but where do you find one that measures in bean pounds per square inch? and wouldn't the methane mess up the reading? since it's less dense then air

lostforawhile
02-14-2008, 04:34 PM
here you go, leave it to the search wizard http://www.poopreport.com/Doctor/Knowledgebase/psi.html

2ndGenGuy
02-15-2008, 08:04 PM
^^ LOL. I suppose Taco Bell could build excess blow by as well.


But guess what. I seem to have fixed the problem.

I did two things.

1. New valve cover gasket. The other one I used was new, but must have been sort of rubbish.

2. I split the vacuum line off of the catch can. I ran the other line to that port on the back of the Weber carb. Then I put check valves on both of the vacuum lines. This way when I'm at idle and low speed cruising, the manifold puts vacuum to the crankcase. And under load, and high speed cruising, the carb creates the vacuum in the crankcase.

The setup actually emulates Hondas crankcase venting system. There's a little mini canister under the stock air cleaner. Instead of using a vacuum port on the carb to depressurize the crankcase, the pressure in the air cleaner itself drops. There's also a vacuum line to the manifold off of the stock little canister as well too.

So maybe a freshly built motor like this just creates a lot of pressure, and after a bit of driving, it will calm down a bit. I'm still kind of afraid though that it's a sign of something bad and that I might be covering up the symptoms. I guess I'll keep reading online, and get to a leakdown test when I get a chance...

2ndGenGuy
02-16-2008, 01:33 AM
http://i66.photobucket.com/albums/h256/jgturk/81%20FSM/CrankcaseControls1.png
http://i66.photobucket.com/albums/h256/jgturk/81%20FSM/CrankcaseControls2.png

2oodoor
02-16-2008, 03:37 AM
voila
you are on to something there, the oem pvc system is "internally calculated' to handle that particular engine, just as pvc valves are not intended to be universal, they have applications for each engine for how much vac it takes to toggle it.

lostforawhile
02-16-2008, 09:35 AM
i forgot about that system the seperator is on top of the valve cover not on the back of the engine. and it has that little piece under the air cleaner. on that setup a bad valve cover gasket will def cause a problem.

2ndGenGuy
02-16-2008, 10:01 AM
Yeah, I'll have to take pics of it sometime soon here. But even with the separator in the valve cover, my catch can still captures a bit of mayo. I'm okay with that though, beats the hell out of reburning that crap. I'm sure part of that is what turns into carbon buildup.