engine rebuild questions (1 Viewer)

[offcamber40]

I am going to be a basic engine rebuild while I have my motor apart. Compression was good when I pulled the engine, but I am going to replace the rings while I am in there. With the pistons and rods still in place, I have significant side to side play where the rod hits the wrist pin in two cylinders.. Is the wrist pin replaceable witout replacing the pistons, or do I have to do both? Also, there is no significant wear on the cylider walls which was not expected. There is some scratching on the spark plug side of the wall but that is minor. It looks as though the cylinders were honed at some point and there is absolutley no ridge at the top of the cylinder wall. Its odd becasue there is no sign that the engine has ever been pulled before. What tool do I use to determine if the boring is still stock? Last question, what do you guys use to clean the motor internals and block with? Someone I know suggested a combo of kerosene and Gunk degreaser.

Mike

 

[roscoFJ73]

The wrist pin is usually available as a separate item on most cars.
To measure the cylinder bore you use micrometer that can measure internal dimensions.You can usually hire one.It will tell you if your cyl are out of round as well.
To clean your block,that mixture you mentioned is ok but I like to use 99% liquid hydrocrbons with an emulsifier that turns white when you wash it all off and gets all the oiliness off.

 

[offcamber40]

rosco,

not to sound stupid, but what are liquid hydrocarbons and where does one purchase them?

 

[roscoFJ73]

Degreaser comes in 2 types.One is a detergent based stuff which dont work on the thick stuff.The other stuff is a solvent and provided you dont allow water to mix with it can be used over and over .BP,Mobil make it and I buy it at my local parts store or hardware in west aust.Comes in 1 gallon cans.GREAT for washing the concrete driveway and hose off with the garden hose.

 

[offcamber40]

Ok, now that I pulled the pistons out, it makes sense why there is sided to side play at the wrist pin, they are supposed to be like that.. LOL. Anyway, checked the clearances on the rod bearings, and they were in spec, but barely. I am going to replace those. Thrust clearances were in spec as well. Pistons slid right out with no problems. Im going to replace the rings because #6 compression was way down. Gonna check the mains, but I think they are ok. I had no signs of main failure anyway.. I am having a hell of a time trying to get the cranksahft pulley off. I should have loosened that while I had the engine in the car. As soon as I get the pulley off, I will be pulling the cam. Do the bearings come out with the cam? I think that one of my timing gears is loose, it makes a pretty good tapping noise when I spin the crankshaft back and forth. Looks like ill find that out tommorrow. Will any harmonic balancer puller work on this pulley?

 

[Gumby]

Is the engine out of the truck? If so, you just can't beat having the engine hot tanked. You'll need new freeze plugs and cam bearings, but it's a beautiful thing. See the engine rebuild thread on the 80s list for some serious engine porn.
My 350 heads are going in next week.

 

[offcamber40]

Yup, engine came out a couple of days ago.. it has been dissasembled and is awaiting parts. What color was the block stock? Im gonna paint it while its out?

 

[Sir_Titus]

FOR THE BORE MESUREMENT USE A SNAP GAUGE AND THEN YOU CAN MIC IT WITH AN OUT SIDE MICROMITER

 

[pvaman]

hot tanked. What exactly does this mean?

 

[tres]

acid bath

correct if i'm wrong but i thing thats what man-a-fre described it as

 

[bobrose]

yes, hot tanking is an acid bath. another do it yourself option is to use oven cleaner spray, works great. that and sea foam

 

[cruzer]

IMHO since you have the engine out and torn down you should

A) hone the cylinders because you are putting new rings in
B) replace all rods and mains even if they are ok...it is only going to get worse. My dad spun a bearing while driving his blazer and to be cheap he only replaced the rod bearings. He inspect the Mains and they were "ok" Well guess what as soon as he started it up it was knocking...so guess what? in there again we had to go!
C) Hot tank it while it's out and paint it. Should be pretty cheap and make it look like a million bucks
D) make sure your head is in good shape or have that rebuilt also..make sure it's flat. I rebuilt my engine and ended up pulling the head off again because i didn't get it decked because i thought it was "ok" It caused my truck to blow radiator hoses and then it did over heat while on the highway.

HTH

Stew

 

[cruiserman]

I would just do it all if you've got the dough. Your call on replacing the pistons, but I would do all the bearings and rings, and hone the walls. You can use a telescoping gauge and a micrometer to do bore measurements. Measure at thrust and axial directions at 3 bore depths. The 2F manual should lay it all out for you.

Hot tank the block, and paint it with engine enamel. Good time to surface the head and block and go through the valves.

The snowball just keeps on rolling . . .

 

[pvaman]

where can you get the engine hot tanked -- does a typical machine shop do this?