Bad News Fellas....how The Gas Is In The Oil

did a more thurough leakdown test today on my rebuilt motor with around 400 miles on it.

87%
89%
89%
87%

based on 100psi pressure

left the oil cap off and you could see the smoke being blown out really good and hear it real good too. This really sucks but I refuse to give up, Guess I will be saving 1600 for a Jasper motor.

There is supposed to be some leakage from the pistons, not alot, but some. Otherwise your spark plugs would shoot out when you went to change one. How much of a gap was there between the ends of the rings when you put them in? Or did you even check it?

i didnt check that... i should have.

people tell me there should be 95 - 99% on a new motor and 90 - 94 on a motor with 100,000 miles on it

[cybermrc]

Yeah but your rings are all washed down with gas. Try it again with a squirt of oil in the cylinders

and what if the readings are higher??

hmmmm My newly built motor has only 110 110 115 110 compression

I am going to try unhooking the turbo and turning the fuel pressure way down (enough to keep it running good)

with the turbo unhooked it wont be as apt to push gas past the rings and they will be able to seat better

I am running a stage 3 comp from fwd and 804 injectors (these injectors are weird because I hit 20lbs of boost on them with no detonation, I bet they are flowing at 38lbs like mopar claims they do)

I only have around 300 - 400 miles on this motor and of course with the gas getting in the oil by getting past the rings they are never going to seat

[turbovanman]

Quote:

Originally Posted by chatterx hmmmm My newly built motor has only 110 110 115 110 compression I am going to try unhooking the turbo and turning the fuel pressure way down (enough to keep it running good) with the turbo unhooked it wont be as apt to push gas past the rings and they will be able to seat better I am running a stage 3 comp from fwd and 804 injectors (these injectors are weird because I hit 20lbs of boost on them with no detonation, I bet they are flowing at 38lbs like mopar claims they do) I only have around 300 - 400 miles on this motor and of course with the gas getting in the oil by getting past the rings they are never going to seat

I wouldn't worry too much about your leakdown yet! 400 miles isn't enough to have them seated 100%.
What is your air/fuel guage reading and manifold vacuum at idle?????
110 compression is low, maybe your cam timing is off or an aftermarket cam?

cam timing is pretty much dead on as there was no air escaping the valves during the test. air/fuel guage bounces back and forth between lean and rich pretty slowly

sometimes it hangs in rich and sometimes it hangs in lean for a quick second. vacuum is at 18 - 20


the car does miss at warm idle. if i unhook the coolant temp sensor it will not miss one bit (but it will run rich) In fact it has a strong idle too with it unhooked

I tried a new sensor but no go.

what else can mess with the spark advance??? I have replaced the coil, hep, wires, plugs, rotor, and cap, distributer seems fairly new ..... its a reman with the shutter wheel riveted in

no codes are being thrown

[Orangetona]

Well, if the guage is pretty slow at idle, your O2 sensor is fouled. What that has to do with anything? Well I have no clue.

gauge isnt super slow it bounces fairly well but not as fast as at cruize. O2 sensor was replaced 150 miles ago with a mopar brand one

[Traffic80]

.....

whats that all about .................

[eef mcglikn]

when giants build really strong motors and don't put them to work...they might not seat the rings properly.......they also might build up a wear pattern not good for flogging the motor like naughty gretchin ......ooops.....

do your normal wear in ......then beat the motor ....lose all respect for it.....

if your rings are a tad bit off ....they will still be a tad bit off...oooops sorry..lets try this...
OFFICIALLY
i recommend you disasemble the motor and refit all the parts... also try asking the people who honed the block what to look for on wear in....

HONED....HONED....WE DON'T NEED NO STINKING HONED....

eef

[eef mcglikn]

or

HONED.....HONED.......I HAVE NO HONED....COUNT DRACULA

eef

[turbovanman]

Well honestly, you got me stumped and without actually seeing it, I have run out of ideas to throw at you. Good luck,