Hello again, listers!
As I have reported before, I am attempting a "first time" engine overhaul on
TS15848E, the TR3 engine that was in my TR2 (TS7690). My engine was running
when I tore it down, but on inspection it was determined that the crankshaft
was shot and the head had a one half inch deep crack starting up the stud
bolt hole between cylinder two and three. The quest to find a decent
"uncracked" cylinder head and a crankshaft suitable for grinding is over (I
think). I was given engine #TS7257E. This was an original TR2 engine. It
did have low port head and smaller intake ports. (My manifolds would not
have worked.) After tanking and blasting, this head showed a slight crack
in the "dome" above and between valves 7 and 8. Although the crank from
this engine was badly rusted, it had not been previously ground and it is
was recoverable. It is now ready to go after grinding the mains .010" and
the "big end" journals .020".
I popped out two of the cylinder sleeves on engine 7257 (one was broken at
the bottom) and I had the engine tanked and blasted with the idea of giving
it to the local High School auto shop as a "static display" to show an
example of a wet sleeve engine. We are a very rural (agricultural)
community and some would find it novel that a British engine developed for
sedan car would also serve as an engine for a sports car and also for the
Massey Ferguson tractor.
Of the five cylinder heads I bought at auction recently in Taylorville,
Illinois for $7.50 each, three showed some kind of cracks on being
magnafluxed (again the center stud bolt holes and one was cracked all across
the top between the valve guides - probably frozen). The fourth of the five
heads had a drill bit hole through the aluminum plug on the top and in the
center of the head. This one was tanked, blasted and magnafluxed and
appears to be ok. ???Does anyone know why those round plugs are there???
I have had the aluminum plug welded. Does this plug go to the water jacket
and does anyone foresee any potential problem in using a head that has had a
weld on this plug?
I noticed that the fifth head I purchased at auction was slightly different.
I found some different numbers on it and upon checking Bill Pigott's book
and the "chart" for TR2-3-4-4a heads I found it was a TR4A head. I wondered
when I removed the valves why this one had the same size valve stems for
both exhaust and intake and only two springs on each valve. I went ahead
and had that one tanked, blasted and magnafluxed and it appears to be good
too. Does anyone need a good, bare head for a TR4A?? Since I probably
won't have my car up and going this summer, I thought that when I go to some
events I could take the bare block, sleeves and the different types of TR
heads and make a sort of information display.
I would appreciate hearing some opinions on a couple of rebuild issues I
need to make some decisions on.
Should I now rebuild engine block #7257E (TR2) or the TR3 engine that was in
my TR2 (#15848)??? I was originally planning on reusing the cylinder
sleeves, pistons, rods and block from #15848. Now that I see how nice the
tanking and blasting turned out on #7257, I am thinking of using that block
This would get me closer to matching numbers, but several folks have asked
"Who cares?" on the numbers issue. The sleeves from the TR2 block were
badly rusted (one broken) and there was a slight chip out of the engine
casting on the bottom of cylinder #3 where the sleeve was broken. This
engine had been pulled apart about twenty years ago and someone had tried
unsuccessfully to hammer out the sleeves. The absence of pistons and rods
contributed to the extensive rust on the crankshaft (along with the mouse
nest I found in the oil pan). I do not see any evidence of a "shell"
bearing for the camshaft on the older block. Since I have not removed the
cylinder sleeves from #15848, I cannot get a good look to see if the newer
block has these. Should this be a significant factor in deciding which
block to use? Can used cylinder sleeves be removed and then reinstalled
with new figure 8 gaskets? The sleeves from the TR3 engine originally in my
car are 86 mm., but the pistons are stamped .030 on the top and center of
the piston. Is it common to fit a piston normally measured in metric units
(86 mm) oversized in thousandths of an inch? I do see ring sets sold in the
catalogs for 86mm - .030".
I have changed my mind on reusing the head stud bolts from my original
engine. I showed the notice on "stretched" bolts in the Moss catalog to my
machinist and I asked if this was a real problem or a sales pitch. He
assured me that it was probably a real problem and that I would be well
advised to get new bolts. Would the listers agree on this? Now here is
another question: Are the different bolts that appear in the catalogs
different because of the blocks or because of the difference in the heads?
(I suspect the latter.) I have removed the studs from the older TR2 block
which had the low port head. The 1st, 3rd and 5th pair were all the same as
were the longer 2nd and 4th pair. There was no difference between "left
hand" and "right hand" stud bolts. I suspect that when I remove the bolts
from the TR3 engine (if I can) that I will see left - right differences and
that this will be because of a built up "boss" on the bolt hole in the head.
I know I am going long, but just a couple more questions please. Before I
order parts, is the extra cost for "stellite" exhaust valves worthwhile?
>From the numerous heads I have removed valves from, I have seen several
broken or burned exhaust valves (almost always #3 cylinder). (This was also
the bad valve in my original engine. Is #3 exhaust valve a common
failure??) I have seen an engine lifting hook and eye bold sold in one of
the catalogs. Are these easily fitted to the TR2/3 engines and would this
be a good purchase?
Any other tips and suggestions the list might offer would be appreciated. I
hope to order some parts (at least valves, valve guides, crank bearings,
thrust washers, rings, and small end (wrist pin) bushings) later this week.
I am beginning to think there is an outside chance that this old growler may
actually run again someday!
Again, sorry for the length of this posting and I thank everyone in advance
for any reply you may make.
Respectfully yours,
Rob Blubaugh
Rensselaer, Indiana
///
/// triumphs@autox.team.net mailing list
/// To unsubscribe send a plain text message to majordomo@autox.team.net
/// with nothing in it but
///
/// unsubscribe triumphs
///
///
|