6G Celicas Forums

yes. things that were wrong with the engine:

1. the oil control rings were just old and worn and got gummed up with oil so they sunk into the piston and since they didn't sit where they should oil just went right past them and got burned on the cylinder walls.
the oil control rings...

sit in the bottom groove of the pistons...

and are held in place by another ring similar to the compression rings (shown below. they go in the two top grooves in the orientation shown) but are a little thinner


2. the thrust bearing was a little worn and had some play. this was just due to the added strain on the crank from it being attached to a manual transmission.
the thrust bearing...

sits on either side of that middle seat in the grooves on either side




all the other bearings and seals were in pretty good shape, although I am still going to replace them all

awesome! thats a pretty big crank, i was surprised. very clean, esp the head.
you guys arent waisting any time either jeeze.

Thats awesome ! This is a project I have been wanting to do for years. I'm happy to have donated my engine to your cause

Keep the thread flowing like this. Its great to see what was the original problem, and what other parts started to fail because of it.

Take pictures of the intake and exhaust posts on the head once you've cleaned them up. Also, take pics of the bottom of the head.

Nice thread

im going to take a guess and say you used mobil1, jeff?

ON A 7A! Are you crazy ? Just used regular sludge for that engine.

hey, this is very interesting for me cuse i am on the same route, how much NA power can u get out of a 7a. Well i really look forward to seeing pics of your progress. Hope all goes well. My two cents, if you have the money send the head of to Extrude Hone, its a process where they push an abrassive material through the entire head (Intake and Exhaust) and it polishes the sharp edges, increases flow and helps for breathing, the process costs $650 for our head, ive called them before to find out. Let me know if you need more info. Good luck

Matt

I can't wait to see how this turns out. Looks like fun.

and it looks that good? crazy. guess all the oil brand debates just got thrown out the window.

stef, i dont know how crazy you want to go with this build up, but if you are really planning to turbo, i would upgrade the pistons, rods, and headgasket, and do the cam regrinds, as well as replacing any rubber seal/gasket. then you would have a strong and nice flowing motor thats ready for the abuse of a turbocharger.

wow... thats an insane price for that. we already did that this morning, took about 20 mins. I'll have pictures soon.

I spoke to a friend of another tech about machining the head and it sounded like all he was going to do was clean it and make it look pretty and charge me $70. its not that dirty, we can clean it at work. if we have the right tools to port match the intake and exhaust we'll do that ourselves too. I can't imagine a 5 angle valve job being too precise either in which case we can probably do that too. we'll see how it goes

to find the size of the main bearings...


for the crankshaft...


there are 5 numbers engraved on the corner of the block (top and bottom)....


that correspond to 5 numbers engraved on the crankshaft itself...



you add the number on the crank to the corresponding number on the block.
no number means 0. so the 01 on the crank pictured combines with the 2 printed on the block to come up with a #3 bearing.

that's looks amazing, makes we wonder why i didn't pick up to being a mechanic, regretting it now, but that's looks awesome

I cleaned and painted the block yesterday...


and we honed the cylinders. I don't have a picture of the tool we used but it looks like a bunch of wire bristles with balls on the end attached to a drill. you have to break the glaze on the cylinder walls in a crosshatch kind of pattern so the oil sticks better...


and today we just re-ringed the pistons..


there are two thin rings that go above and below the oil control rings in the bottom groove and the top two are the compression rings. you want to place the openings in the rings on alternating sides and always right above the wrist pin since that takes the least stress. so in the picture the opening in the ring under the oil control ring is facing back, the one on top is facing forward, the first compression ring facing back (there is a "2R" written on it that should be facing up), and the top ring facing front. they fit very loose like that so as to make a tighter seal with the cylinder wall when installed.



we can't do much else until the main bearings come in (probably Monday) since we need them to put the bottom end back together. we want to finish the bottom completely before starting on the head, just to keep things organized.

This post has been edited by hurley97: Sep 13, 2007 - 6:10 PM

if your not gonna get the pauters and want a little extra strength id shotpeen the rods while they are out. its cheap and it gives a little bit of strength to them

reminds me of rebuilding a cummins engine, same process but cummins is like 10x bigger!

this has to be the most interesting thread ever!
keep up the good work!

I personally would check all parts with a micrometer and
make sure crank, rods, oil pump meet all specs.
Thats kinda my thing though. The thrust bearing journal
looks a little scuffed at least in the one pic.

Steff this thread is awesome! keep it up

from what I hear the pistons and rods will more than stand up to the abuse of a turbo (I'll save that for when I rebuild the engine thats in my car since it'll be much worse and probably need a re-bore anyway), the head gasket is already metal, I will be replacing any and all seals/ bearings I possbily can, this is going to be like a brand new engine when it goes in, I do want to smooth out the head some to make it flow better, right now I'm thinking about the bigger cams.

WebCams has done a grind for the 7A before and it would cost about $575 and about 3 weeks. Reasons I'm not sure about them right now is 1, they cost more than the rebuild parts 2, I'm not sure if I want this engine to sit at work for another couple weeks and 3, I really don't know how they will affect the car since they tell me it has only been done twice before. Also, what I kind of want to do is dyno the stock re-built 7A, then with just the cams, then the turbo. still thinking about it...

Steff i love this i feel like im in class Your pictures and descriptions are amazing!

I wish i had someone around to learn off of, this is a GREAT opportunity.