Using oil issue

-
L2 sucking oil, lotsa ash. L4 not so good.
Tighten intake bolts, clean plugs, repeat .
On-end shot of 2/4 plug tips may be helpful.
 
Newbomb Turk said:
Make sure it’s not pulling oil through the PVC system.

I’ve seen engines leak pretty well (under 15%) that used oil like a mother.

Most of the time the second ring was killed and the oil rings were marginal at best.
Click to expand...
Not saying that a compression test and a leak down shouldn't be done but let me relate what happened to a customer last summer.
Customer bought a new 602 crate from us and had us dyno it. Motor dynoed fine and made slightly above average power for a 602 crate.
He put the motor in his race car and it ran fine the first couple of nights. Soon following he noticed a miss in the feature. He pulled the plugs and had one that appeared fouled. Replaced the plug and the motor ran fine the next race but at the following race started missing again. He pulled the plugs and the same cylinder was fouled again.
This time all cylinders were compression checked and leaked down. All cylinders checked good in both compression and leak down. Customer tried a different carb but in about 2 races the plug fouled again.
We borescoped the engine and the cylinder in question looked like the other cylinders. Nothing out of the ordinary.
The motor was still running great so the customer finished the last few nights of the season preemptively replacing the sparkplug.
At the end of the season the motor was taken to a certified crate rebuilder who repeated a compression, leak down and bore scope of the engine. Finding nothing the motor was disassembled. It was discovered that the oil rings were mistakenly left off the piston from the cylinder in question when it was assembled new from the factory. Only the top and second rings were on the piston.
My take away from this is that a compression or leak down test are not good indicators of the condition of the oil rings.
 
It's possible that the rings have stuck from the motor sitting that long. When we dyno restoration motors we encourage the customer to let us fog the motor for them when we are done dynoing.
 
Inertia said:
L2 sucking oil, lotsa ash. L4 not so good.
Tighten intake bolts, clean plugs, repeat .
On-end shot of 2/4 plug tips may be helpful.
Click to expand...
Inertia said:
L2 sucking oil, lotsa ash. L4 not so good.
Tighten intake bolts, clean plugs, repeat .
On-end shot of 2/4 plug tips may be helpful.
Click to expand...

IMG_0162.jpeg


IMG_0163.jpeg


IMG_0164.jpeg


IMG_0165.jpeg


IMG_0166.jpeg
 
An engine sitting for a very long time, if not properly prepared, can literally let the cylinders with open valves " breathe".
Suck in cold damp air, expel warm air, day after day can form rust patches in those cyls.
Lotsa these engines will seize, others will run with reduced power? from these cyls, and only discovered at tear down.
Not saying this is the case, BUT it is one of the reasons I rotate the crank a few times a year on racecar engines, (should do all).
A bent pushrod or stuck valve could cause a similar condition.
 
Last edited:
I’ve had two motors sit for 12-13 years. I did nothing to prepare the for the years to follow. They sat with zero attention the entire time. Primed the engine and turned the key. Ran just fine.
 
BSB67 said:
I’ve had two motors sit for 12-13 years. I did nothing to prepare the for the years to follow. They sat with zero attention the entire time. Primed the engine and turned the key. Ran just fine.
Click to expand...
Except for the 2 rusty cylinder walls.
 
BSB67 said:
I’ve had two motors sit for 12-13 years. I did nothing to prepare the for the years to follow. They sat with zero attention the entire time. Primed the engine and turned the key. Ran just fine.
Click to expand...

Yep, all depends on climate, temp change ranges, humdittity, etc.
I release the rockers/shafts on our cars, non-ohcam.
Rotate the ohcam engines regularly.
 
Last edited:
If it were mine, I'd clean the plugs or new, run it for a few hours, and pull the plugs again looking for plugs that are "different".
I would expect that plug to be wet/oily again.
Sources of oil, - pcv, intake manifold or gasket, valve guide, valve not opening, ring.
good luck
jmo
 
Frank Dinatally said:
Fog?????
Click to expand...


Just one of many videos on the subject. I used to work at a boat shop and at the end of the boating season we would fog the motors as a part of the preparation for storage over the winter.
It is the process of spraying storage or fogging oil either through the intake or sparkplug holes or both in an effort to prevent rust and oxidation from forming on the inside of your engine when it is not being used.
 
You must log in or register to reply here.
-

Back
Top