3 cyl diesel rebuild

I had to rebuild my diesel due to stupidity, I reassembled with a machined crank, all new bearings(supplied by the machine shop) new rings, gaskets.... My question is how hard should the engine turn over by hand? I was told I should of done that before I installed the head. I can turn it with a 3/4 drive breaker bar. Is that too tight?
 

my experience is that it depends mainly on the seals. Rope seals need all of that breaker bar, and you should turn it by hand until you feel that it has relaxed a little. A lip seal will turn much more easily. another thing that can make them turn hard is caps installed backwards.
 
Are the PUSHRODS INSTALLED? What was the bearing clearances(how was clearance checked)..within specs? what was the crankshaft thrust clearance.(how was clearance checked..within specs? What make of a 3 cylinder engine? what was placed on the bearing shells (lube) at installation? How many rings per piston? were cylinders well lubed before pistons installed? did pistons install into bores with out excessive force?
Bob...
 
Ever heard of Plastiguage and did you check the ring gap in the cylinders before installing them on the pistons? I plastiguage every bearing in every engine that I build and I check the piston clearence and ring clearence. I have built a bunch of them in the last 30 years I have never had one to come back because it was too tight or it wouldn't start with the starter.I hear horror stories all the time about people dragging them down the road to get them to start.Not me. If it doesn't turn over easy,it comes back apart.
 
I had a look at some of the CASE STUDY Failure investigations that I was asked to be part of from 1971>2011
(1) incorrect bearings Installed on crankshaft (BRGS. were undersize)
(2) Thrust COLLAR was not installed on CAMSHAFT allowing CAM to move FRWD. binding on TIMING COVER
(3) Incorrect CAP SCREWS used to attach timing cover ...cap screw bottomed out against drive gears
(4)BRG. shells were installed incorrectly, anti rotational TABS were not lined up with machined grove in BLOCK
(5)insufficient butt clearance on piston rings
(6) carbon had not ben removed from ring grooves properly before installing new rings
(7)Person installing all new parts "ASSUMED" parts were correct and never checked anything against OEM SPECIFICATIONS!
(8)Piston WRIST PINS installed with lack of clearance in either PISTON BOSS or SMALL bore of CONN. Rod
(9) Person assembling engine never used Prussian BLUING to verify contact of Crank Journals with BRG.INSERTS...should always do after crank has been GROUND or BLOCK line bored
Please let us all know what your finally done to resolve problem
 
Sounds like you need to get a mechanic to go over your assembly job before you cost yourself a lot of $$$$.A similar thing with a neighbor he was going to replace the crank in a JD 950 well its no job for an amateur and he found out the hard way ruined his new crank and the block.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top