The past few months I have been trying to figure out what the heck has been wrong with my motor. After doing numerous compression tests, I found that I can only muster 125 psi all around. I have tons of blow by and the power is just not there. I was told a way to determine your problem was to hook a air compressor into the cylinder, and listen for leaks, well i did have a leak and tons of the air came out of my breather. It is a Mexican 302, I would like the entire bottom end inspected, re ringed etc. How much am I looking at for block to be rebuilt and just the block with out any bolt ons installed. Soo basically I would send them my block with pistons, connecting rods and crank and get it back the same, I will remove and install the new cam. What size over bore should I go with? Should i get over sized pistons or get a sleeve? I was also considering, getting the block bored, and assembling it my self and have it balanced by a machine shop... but that is probably not very practical. thanks guys Mike also, I found a nice running c-4 outta 66 with a straight 200. Will that bolt up to my engine?
Your looking at least $1000 to have your short block rebuilt with boring and new pistons. maybe more , maybe less, depends on how you shop around for the parts and choice of machine shop.
Mike Phoenix engine rebuild 7th ave south of DeerValley cost $900 to $1000 depending on what you want. To answer your question on the c-4 the bell housing and plate wont match up but you could use the c-4 when you get the bell housing/plate fix.
alrighty, Should i pull the motor and take it to a machine shop soo they can determine the overbore I should go with and if i need new pistons? or can I do that at home? I would like to know as much as possible before I go into this. Thanks Mike also what if I use the my current bellhousing and "plate" from my 302. will i still need more stuff to get the 6 cylinder c-4 to bolt up? Mike
I'm not sure how well a 6-cyl c4 will hold up to a v8. I really don't know if they are different, but I read about a guy with a 351W and his 6cyl c4 not getting along. I think he broke it right off the bat. I could definately be wrong-- hopefully someone else will know for sure. Just don't want you to get stuck with something that's gonna possibly break.
Gottcha, L-man 66coupe: You are overlooking valve leakage? 120 PSI on ALL cylinders suggests a gauge or test procedure problem rather than rings/pistons problems. Normally there will be a variation of compression reading rather than a constant reading (like 120 PSI). Replacing the rings/pistons without doing the valves is shortsighted. Did you remove ALL of the spark plugs before performing the test. Any used transmission should be checked out and serviced by a pro.
I bought the heads about a year ago from 2bav8 and he said they were inspected and were fine. I also did fill the cylinders with air and found that air was leaking alot out of my breather, I also used the tool that sniffs the coolant and came up with no headgasket leaks or any exhaust/gas fumes in my coolant. I ran other tests like vacumm capabilities when cranking over and i got a fluttering gauge. The car burns tons of white smoke at idle and doesnt die down at all. Mike
"Burns tons of white smoke at idle"? "Doesn't die down"? White smoke is usually water vapor caused by an internal coolant leak into the crankcase or combustion chambers. Better determine what is happening before you tear it apart.
I need a fast answer before I pull the motor and have it checked by a machine shop later this week. thanks Mike
Is the car using coolant? Are there bubbles in the radiator when the car is running? Is the oil milky colored? Did you remove ALL the spark plugs before you tested compression? Quick enough?
How About, Pulling the plugs and smelling them for coolant, or wet conditions. White smoke at idle is usually a bad Head gasket. Simple Check. PB
No not quick enough, pulled the engine and tranny today I also did every single one of the test you said, and yea I did pull all the plugs during the compressio test. Ill get pics of the removal later, took a total of 4 hours to get the engine out, another 4 getting cleaned up and getting the engine and tranny seperated and in my Jeep ready to take to a machine shop for inspection. Mike
