[TR] TR4 engine rebuild

Lee&John Howard leejohn7 at gmail.com
Thu Feb 14 17:56:17 MST 2008


Hi all

I'm at the point of dealing with my broken crank engine. I've stripped the
engine and liberated the good crank from the spare engine. I've discovered
that:
1. The new crank does not turn in the old block when torqued down with the
new crank's bearings (from the spare engine). This suggests that the block
was twisted when the crank was broken, right? Meaning I need to get the
block "line-bored?"  The crank journals measure very close to spec, but
should I grind to .010 under anyways to be sure of a good and easy turn?
2. The oversized piston sleeves are ridged at the top, meaning they have
developed a taper, correct? So I should replace the sleeves? Hopefully I can
make do with the existing upgraded pistons.
3. The cam is shot, with pitting at some lobes. I have the specs of this
upgraded cam, and can have it reground to those specs. Is that a good idea,
or should I get a new  "street" cam, such as the old "D" cam. I think it
might be best to replicate the old cam since the engine was built around
that in the late 70's.
4. I am having a valve job; valves badly carbonized and some aren't seating
well. The machinist thinks the seats are hardened, but if not, I'll have
that done.
5. I'm going to do my best to really seal up this baby. The last one I did,
on another engine, ten years ago, puddles wherever I go.  A speedi-sleeve at
the front crank seal? On the rear seal, new but stock size "oil seal
assembly," with well stuffed felt seals?  I think I'll buy Moss's crank
alignment tool to make sure everything is centered correctly. Any
suggestions?  Should I mate the front and rear caps with hylomar or
something? Should the gaskets be dressed?

Whoa, that's enough. Sorry to be so wordy.

Many TIA

John Howard
64 TR4 CT35800
65 TR4 CT38746


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