engine and drivetrain Bottom End Rebuild

[Guest Anonymous]

Bought a 1973 that needed a valve job as a friend owed me a favor and had a 1971 parts car. He took out the engine, sent the head in to a machine shop, honed the cylinders and put in new rings, seals, painted the engine, replaced my transmission with the one from his parts car which was in better shape (mine had a synchro problem 3rd to 2nd), new water pump & thermostat. Turned out as he owed me a favor he did cut corners, no new oil pump, didn't do main bearings or rod bearings or anything with the timing and didn't tell me. Naturally he claims we are even and blames me for over-reving the engine or not letting it warm up again.

Ran fine for a week, a friend took it to a paint shop and coming back after getting painted, said it was sputtering and died. Had it towed back. I went to start it thinking the fuel pump was bad. In fact the pump was leaking at the back, but the problem is that I have a rod knock. He swears the car didn't overheat and he didn't hear the knock.

I pulled the sparkplug wires to see if the sound was from any particular cylinder but couldn't tell any difference. Didn't put a piece of hose to the engine to see where the sound was centered but it seems clear it is a rod knock. Other than being real bummed out, I need a game plan: abandon ship and bail out, if I get a bottom end rebuild what should I do to avoid this happening again.

There is a lesson in here somewhere on why you should do a rebuild correctly. Now I am worrying about the old pistons and connecting rods. If I just have someone tear down the motor to drop the crank and have the connecting rods measured and resized, should I just have them do an entire bottom end rebuild with new pistons? Can I reuse the head gasket which is a month old?

At least the paint job came out beautiful so my neighbors don't mind the car being parked on the street while I figure out what to do next. Do I have to pull the motor again or can I try working from the bottom or am I looking for the same trouble.

I really wish the bottom end was rebuilt to start with.

[Guest Anonymous]

ed,

i just finished rebuilding my bottom end after one of my pistons blew a hole threw the top. are you willing to rebuild it yourself? if you are you can save yourself a whole bunch of money and it's kinda nice to know how your m10 works. i would say that you should just rebuild the bottom end and do it the right way. i'm sure there's someone out there that has a magna fluxed block with new rods, pistons and bearing waiting for you to pop into your car. i lucked out and bought a set up like this from a fellow bay area 02 memeber. before i started my rebuild i had never even taken anything off my motor, except for the water pump. and to answer your question about the head gasket, no. they are only meant to be compressed once. i don't know if that helps or not, but i hope you get a better build bottom end the next time around.

good luck,

evan

[Guest Anonymous]

Did some autocrossing and over revved my engine. Took the oil pan off and took off the rod end caps... sure enough rod bearing no 3 was at the copper part and had peices missing. I was sure that I didn't drive it much when I first heard the knocking. you can push the pistones up a bit to get the bearings off.. just don't push them too far so not to bend the valves above. taking the plugs out makes it easier. Measure the rod journals a few times to make sure that they haven't ovalled. If they have your shit out of luck and need to machine the crankshaft. I was lucky enough not to need that. If your good and circular, install the new bearings and bob's your uncle. If it's a main bearing knock.. out comes the engine. As for the waterpump.. get a new one for insurance.. having the fan hit the rad would really suck. the oil pump.. if you're inspecting the rod journals, take it off and check the tollerances in the gears, and before removing it, check the chain play,.. if need be you can install shims to tighten it up.

Good luck

Roman