Question for experienced engine rebuilders

I have been trying to decide weather or not to rebuild my fireball 198 that came in my 65 cj5 or find a 225 and rebuild it. So I decided to take apart the 198, boy was I suprised this motor is imaculate no sludge very very clean condition. I think I can get away with new rings and bearings timing chain set etc. Now to my actual question when I removed the rod caps the crank seemed to have what I would call some light scratching you could only see it if the light hit it right and you could not feel it at all. should I go to the trouble of having the crank done or should I be ok? Also this was not on the main journels and it did not seem to be on the inside surface of the rod bearings or was this on all the rod journels this leads me to think this was there when the motor was last assembled. Any sugestions?
Thanks Steve

 

I'd think that a few scratches wouldn't ruin the journal. You might try a little polishing of the journals with some crocus cloth.

There's one thing you have to do when rebuilding though - measure! The only way to tell whether you can reuse the crank without turning is to measure the diameter of each journal across the face and at different locations on the journal. Unfortunately, cast iron cranks (like this one) are soft and will be damaged if the bearing or lubrication fails.

If it were mine, I'd be very willing to put it together with honing, new bearings and rings, and a new timing set if the journals measured within spec. However, your tipping point re rebuild or replace has to account for the higher cost of fixing a 198 v. a 225. Measure everything, add up the costs, and choose.

 

I agree with the above. If you can't feel it, or catch a nail on it, then you'll probably be fine. I would measure it carefully though. Did it run before you tore it apart? If so did you have good oil pressure? If you did, then I would be encouraged to put it back together with new bearings and gas on it.

On another note, I have a complete (full set) Felpro gasket set for a 198. I was thinking about rebuilding one I got in a '65 as well, until I found a running (almost) 225 for next to nothing. Easy decision for me. If you need that gasket set, PM me and we'll work something out.

 

Whut they said. Especially the measurements and when you assemble the motor everything must be CLEAN. When you think you have everything clean, clean it some more. I've seen more engines fail because of lack of cleanliness and proper measuring than anything else. Nickmil.

 

Thanks for the input .
Yes it was running before i tore it apart,oil pressure I dont know, no gauge no light. Jeep had been sitting idle for a Quite while before I got it . Measuring was my next task. Having a hard time finding specs for the crank journel measurements. If anyone has any links or info for detailed engine specs for the 198 please let me know. Have been checking on parts avilability and cost, a lot of stuff interchanges with the 225 no big cost problems just finding it all and what the detailed specs are.
Thanks Steve

 

Parts arent all that hard to find . The specs are harder to find. 135 hp isnt so bad and the jeep is already set up for it. Ill keep a spare of the hard to find stuff . And once its rebuilt Im good to go for many miles. So I think cost wise it will work out ok.
Steve

 

Its a jeep park it on a bump and pop the clutch on the way down and your on the way. Sparky I am suprised

 

And I live in Florida not a lot bumps here.

 

Ahha you are right it is hard to be under the hood and behind the wheel at the same time. But I say when in doubt park on a bump you never know.R)

 

I am very interested in the gasket set set pm me with details.
thanks Steve

 

I think I would take that decision along with what the machine shop advises.

You have the engine this far apart -- skimping now could be false economy.

The machine shop could advise you whether to polish or turn the crank.

You can still take your own decision, but that would be one more data point for input.

The other thing that I would be sure to do is to have the rods and rod caps checked for roundness. The shop I use charges $12 per rod to check roundness. These engines are pretty sensitive to rod/cap roundness, and you certainly wouldn't want to spin a bearing just to save 72 bucks or so.

good luck

kamel

 

My experience with machine shops is that they very seldom turn away work. If you take the crank to them, chances are they will advise it be turned. Of course, I'm sure there are some shops out there that will turn away work that's not justified... but Darwin is working against them. IMO all you can expect is that they will do the job that you ask for at a reasonable price and competently... but don't expect them to advise you on how to save your money at their expense.

The only way you're going to really know the condition of your engine is to measure it yourself. All this worrying about the rod journals may not matter if you find that your engine's already been bored 30 over, and has 20 thou of taper, for example. In that case, you'll need a 60 overbore, new pistons, and I'd have the rods rebushed to match the pistons... probably not worth fixing.

The more information and knowledge you have, the better you can control costs. I'd suggest Tom Monroe's book http://www.amazon.com/exec/obidos/t...104-1271324-5428720?v=glance&s=books&n=507846 if you haven't read it yet.

 

Steve,
These are the Buick specs for the 198 V-6 Special (1962-63):
Bore: 3.625
Stroke: 3.200
Con Rod Journal: 2.00
Main Brg Journal: 2.2992
End Play: .006
I can come up with other specs if needed, I found these specs in a Chilton repair manual from 1964.
Hope it helps!
Joe

 

Thanks Joe, that was very helpful. This board is great.R)