# Rebiulding!



## spat (Oct 15, 2005)

OK, looking for some input from engine builders! I recently bought a 94 Altima with a blown head.

I took the head off this weekend and found rust in the cylinders. I have rebuilt many engines but never one with rust inside. The rust is wide spread but doesn't seem too deep. I am waiting to get the head completely checked before I do anything. The head was blown across 3 cylinders. WOW!! 

It appears the water pump was leaking and they also had that notorius timing cover oil seal behind the cover leak (gravy)! I did a preliminary check and the head is warped. Go figure huh? If the head is salvageble I was thinking of just honeing the cylinders and doing all new rings, bearings and timing kit. 

Below is a picture.



Any tips would be great!


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## cshepard (Oct 6, 2004)

I rebuilt my 93 engine head and I don't recall having that much rust. I did have some similar to your #1 Cylinder. The head was also warped. I did all the work except for cleaning and reshaping. Also had to have the shims grinded to specs. That may have been due to not labeling them when I first took them off. The Machinist recommended that I put the head back in and have him test for compression but I didn't have a way to get it to him. I bet the machine shop can get the majority if not all of that rust off. However, that number 2 Cylinder looks pretty bad. I am sure the machinist will know if it needs replaced or not. Maybe take that picture with you. I was able to get most of my rust off with little effort, but yours may be a challenge.

Mine was caused by overheating and a leaking water pump.

Did you have a hard time getting the intake manifold off? Those bolt locations are not friendly at all.


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## Toolman5523 (May 23, 2007)

Spat, I would carry on with your initial plans that you stated. those motors are pretty tough. just clean the rust up, and you should be fine.


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## spat (Oct 15, 2005)

yeah, I plan to try hoening the cylinders first to see if it will clean up before going through the block removal. I don't have much equipment at home for engine work, just tools but no hoist. I just never dealt with so much rust inside an engine so was curious if anyone had experience in that.

"cshepard" I learned many years ago that it is usually easier to remove head and intake together and then remove intake with the head off of the engine.


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## MickeyKnox (Jun 17, 2006)

engine block is iron. so it gets rusty very easy. 
what's your mileage. 
if it's more than 100-120K you will most probably need to over bore it by one size. I think stock is 89mm. if your rebore your cylinders to 89.5mm(next size I think) you will need oversized rings, which are 89.5mm. next size is 90mm. those rings are sold as stock, 89.5 and 90mm. oh and you will need new pistons. also 89.5mm. machine shop will fit pistons into cylinders and you can assemble the engine block. so machine shop will also have to seal connecting rods to your new pistons. so call your local shops and find out how much all that will cost. used engine is cheaper than rebuilding. I rebuilt an engine purely for fun and learning experience. it is much cheaper to buy used engine than mess around with old. people rebuild engines when they turbo their cars and need forged parts inside. 

with mileage cylinders become oval. the wear out more in the middle than on top and bottom of cylinder. so honing oval cylinder will not make rings seal well. you will have more oil leak into chambers than you have now. 


Use permatex "the right stuff" RTV sealant when you put everything back together. checker autoparts have it.


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## spat (Oct 15, 2005)

MickeyKnox said:


> engine block is iron. so it gets rusty very easy.
> what's your mileage.
> if it's more than 100-120K you will most probably need to over bore it by one size. I think stock is 89mm. if your rebore your cylinders to 89.5mm(next size I think) you will need oversized rings, which are 89.5mm. next size is 90mm. those rings are sold as stock, 89.5 and 90mm. oh and you will need new pistons. also 89.5mm. machine shop will fit pistons into cylinders and you can assemble the engine block. so machine shop will also have to seal connecting rods to your new pistons. so call your local shops and find out how much all that will cost. used engine is cheaper than rebuilding. I rebuilt an engine purely for fun and learning experience. it is much cheaper to buy used engine than mess around with old. people rebuild engines when they turbo their cars and need forged parts inside.
> 
> ...


Not much concerned with current wear on cylinders or out of round. I have rebuilt many Nissan engines and the worst wear I have seen is 0.004" after 264K miles. Of course I will check it after a little honing but need to do a little honing first just to get it smoothed out. If it looks like I can hone it all out without going oversized then thats what I will do. If it does require boring then I will Likely chunk it, don't know yet.

I don't know the actual mileage. I bought it with the OD showing 61K but I doubt that is accurate after giving a good look over the entire vehicle I would guess it has at least 100K probably a good bit more. As a technician, when replacing an OD, I used to use an etching tool to engrave the current mileage of a vehicle in the drivers door jamb next to the ID plate. But I can't find anything on this vehicle anywhere.

I only payed $200 for it so what the heck! Thanks for the input thou.


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## spat (Oct 15, 2005)

Update!

I finally got a call from the machine shop yesterday, they have been swamped. The head is warped .014" and valves are in a bind. Well thats not a complete surprise to me seeing the condition of the cylinders but not what I wanted to hear. He said that he can repair it but will take a lot if work to do so. around $250 total to repair. I told him I will call back later in the week with an answer. Just need to think about it first. I trust these guys, they have been in buisness for over 60 years. The third generation son will be taking over soon. I just wonder about the rest of the vehicle? If I decide to scrap the car I may have some parts to sell. I will post more later. Going on vacation the end of next week.


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## smj999smj (Jan 1, 2006)

I think I'd be pricing a used engine, if it were me.


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