Hi,
Dipping the engine to clean it??? The entire engine??? You must have a "big
tank"... oh, I see ...af.mil domain. Nevermind.
Do a compression test and/or a leakdown test before you start - this will
point out some of the engine's deficiencies _before_ you get too involved.
It'll also give you a reference point after you get everything back together.
Please do this... use gunk or some other solvent to clean the engine
_before_ you take it out of the car. It just makes the job easier.
Then, with the engine out of the car, clean it one more time (it'll be more
accessible). Use Gunk and/or a strong detergent such as Simple Green.
Then start taking things apart.
The key here is - try to keep the crap out of the engine internals. You
won't believe how hard it is to get all the crap out if you don't do it in
this order!
If you plan to hot-tank the block, make sure you have all the parts _on
hand_ before you start (or make sure your machinist can get them for you.)
The oil galleries have two plugs (one above the oil filter and one at the
front end of the engine) that are aluminium, and these will dissappear when
you hot-tank the block. If you don't have the parts on hand or you cannot
fabricate them, you'll be waiting for the dreaded "back order" next spring.
Don't ask me how I know this.
Then, once everything is _real clean_, clean it one more time.
You can't be "too clean".
Pointer - get a set of taps and dies for cleaning the threaded portions of
the block. You need to be totally anal about this if you want to get things
back together with no future problems. Use oil/grease to get the crap to
stick to the taps and then flush with solvents to get the oil out of the
threaded areas. Oh, and you'll need to clean it again when/if you get it
back from the machine shop.
As for what needs to be replaced after 100K miles - bearings, thrust
washers, seals (of course), spigot bush, rings (maybe - but get an "inside
mic" and measure the bores before you order the parts), you _may_ need new
cam followers and possible a new cam (follow conventional wisdom on this:
new cam, new tappets; old cam, old tappets (unless they are hopeless and
even then, be warned that new tappets with an old cam can sometimes invite
disaster (don't ask how I know this, but want to buy a cam with only 11
lobes???) pistons (maybe - see rings), valve guides (probably - I suggest
using stock cast iron guides unless you are really racing then use
manganese bronze (if you can get 'em)). Then just clean up the head and see
what happens. I might also suggest that you get the valve srpings tested to
make sure they are within spec. You don't want to get everything all back
together and then have to do a valve job next year because of a valve
seating problem... Oh, and if the valve seats are nasty, get the three
angle grind on the seats and the valves. And replace the seats - if they
need replacing. If not, save yourself some money... You really do not need
to do anything to make the head "no-lead", contrary to popular belief. Talk
to me off-line if you need more info. on this topic.
To get higher compression, just mill the head. Keep in mind that if you
wind up having to bore the engine, that this will increase teh compression
ratio also, so don't mill too much off the head! The TR6 Comp. Prep book
provides some figures on this topic.
Oh, and I hope your checking account is in good order. You're about to
spend some serious money.
Good luck.
rml
TR6's
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