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How to remove pistons and crankshaft

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2wrench

2wrench

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Got the engine on an engine stand upside down;
removed most everything we could including
main bearing caps. Crank is loose but won't
lift out. One end plate is still in place because
it was left on to bolt the engine to the stand.
Sure I have to remove it from the stand and take off
the end plate for starters; but how do we remove,
then, the pistons and the crank?
Car is '74 TR6.
 
Make a place to lay-out six rods with pistons and big end rod caps, rod cap bolts and big end rod bearings in a way so as to preserve the order of placement in the block. Each rod has two bolts in each big end (crankshaft end of the rod). The big end cap has two bolts. remove the bolts and remove the cap. Push the piston with rod attached through the top of the block. Continue the process for the six pistons. Don't let the piston and rod fall through to the floor and you may find you need to tap the piston to get it through the "ridge" of carbon etc at the top of the cylinder. I use a long hammer HANDLE against the piston to tap it out.
 
Better, IMO, to mark the rods & caps as they come out (if they aren't marked already). HF has an inexpensive set of number stamps that work well for me.

There is also a special tool available, called a "ridge reamer", to remove the band of carbon & metal at the top of the cylinder. I usually don't bother, but if you plan to reuse the pistons or rings, it might be worth investing in one. (Some auto parts stores will rent them for free, just leave a deposit of the purchase price.) Forcing the rings past the ridge may break the rings or damage the piston lands.
https://mgaguru.com/mgtech/tools/ts311.htm
 
2wrench said:
Sure I have to remove it from the stand and take off the end plate for starters; but how do we remove,
then, the pistons and the crank? Car is '74 TR6.
Click to expand...

You need to remove the rear engine plate and then the rear seal mount. Once this is out you will be able to lift the crank right out.
 
MARK the rods/caps. A "vibrating pencil" to etch 'em or a felt-tip on clean parts. Stamping them isn't the best way to do it. And if there IS a ridge, you will likely encounter resistance thumping the pistons out, and may break the old rings and/or damage the pistons in the process. It may be noted that if there is much of a lip it'd be better if the block were cut to the next oversize and new pistons fitted. The bore should ideally be checked for wear with bore gauge by a good machinist to make an evaluation.
 
2wrench....
I've been out of touch for a week or so; doesn't the engine block have a hole where one does not belong from the gudgeon (wrist) pin smacking it after the piston disappeared; you're not considering repairing that block are you?
 
Well, Fellow Forum Members, it looks as though any
effort to salvage any part(s) of my engine is like
a bust.

As figured, and most certainly, the block is wasted
with a huge crack running down its side.

The cam had a rather flat lobe, to say the least.

The crank has yet to be determined....but I anticipate
it's probably not likely worth keeping after over
100K.

One piston is completely disentigrated and the
connecting rod is broken with a hole in the cylinder
wall.

But hey, the dip stick still works, so all I need is.........................................................................................................................................................
 
Bummer!

If the crank hasn't already been turned down to -.040", it's probably cheaper to re-condition it than buy another. But that sounds like the only major component worth looking at.

Did the bouncing valve head destroy the cylinder head too?
 
Good news: short blocks are easy to find and cheap. New pistons with rings cost less than $300. Rod and main bearings less than $100. Find a good machine shop and you are in biz.
 
Vette,

What source are you referring to for the pistons (and other parts)? I noticed that TRF does not list pistons and I want to start to get a list together of "available parts if needed" for the spare block that I bought.
 
Brosky said:
I noticed that TRF does not list pistons
Click to expand...
Huh ?

148118/STD T56 PISTON,STD.
AE17753/KSTD T56 PISTON,STD.
AE17753/K020 T56 PISTON,+.020 IN.
AE17753/K030 T56 PISTON,+.030 IN.
AE17753/K040 T56 PISTON +.040 IN.

They're even having a sale on the AE brand pistons, until Jan 1.
 
Hey!!!

Where did you find that??? I was looking in the TRF Glovebox Companion on line. My bad......

I would appreciate the link Randall. Thanks.
 
The Glovebox Companions are woefully incomplete.

I started with the database search page
https://secure.zeni.net/trf/

then entered "Limit to: TR6", "Category : Engine", and "piston". That only produced one match, which seemed odd to me, so I searched again on the one part number it did show, 148118. That led to the AE pistons.

Just tried it again without specifying "category : engine", and I see there is also a listing for Venolia pistons in standard size :
PN101/STD T56 PISTON,VENOLIA,STD CUR H 0 $129.95
Venolia makes racing parts, so presumably those are stronger pistons than the others. I just learned that Venolia is right down the street from me and has listings for other Triumphs ... I may go talk to them about some Stag pistons as well.
 
But, Paul, at the prices quoted, I think you
want to contact BP Northwest, or someting like
that. I noticed they have an ad now in our Forum.

I must tell you that I was surprised at their
prices as I shopped and compared. So I called the
owner and asked him the question: Why are you able to
sell your parts at such competetive prices and liked
his answer....

Location, much cheaper real estate than Southern
California location (I think you know who he means);
as well as his competition has a lot of money into
catalogs and they carry a much wider assortment of
items in stock and are generally bigger companies
with larger overheads, the result of all of the above.

Being a small business owner...( and I do mean small,)
I can appreciate his answer.

They have been selling parts for 20 years or so and
have a product line with a proven track record....so I
am told.

I think I'll try them out.
 
BPNW parts are limited, but I've never had a problem with out of stock pieces and the quality has always been great - they beat everyone when I did a brake and clutch system overhaul. I'll go back.

Randy
 
TR4nut said:
BPNW parts are limited, but I've never had a problem with out of stock pieces and the quality has always been great - they beat everyone when I did a brake and clutch system overhaul. I'll go back.
Click to expand...
I agree. Service, knowledge and delivery (even to Canada) are all excellent. Their selection is not as broad as the 'big-3' but pricing on stocked items is usually better and quality is good.
 
Paul, it's BPNW and I used them in a tune up on my '74 tr6. The machine shop did not find anything wrong with the pistons and rhe bearings (tri-metal?) looked ok too. I got my pistons with rings and pins for $340 but I think they are 280 now. I don't know or care where they were made as they passed the machine shop inspection and several runs at 5500 RPM's by me. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Thanks guys. It won't be torn down and cooked out at the machine shop for another six weeks, so I have some time to collect parts estimates. I didn't know about BPNW and the engine parts, but I will be checking them out, along with LBC.
 
Just to clarify, in fairness to British Parts Northwest,
it is to say that they focus mostly on engine
rebuild stuff and the like. Inotherwords, you wouldn't
go to them to buy carpet sets or a mirror or something
like that. I think they focus on drivetrain stuffs. That was the point they made as to why they can hold their
pricing down; no books; less employees; lower cost
real estate; less in stocking the shelves by narrowing
the focus on parts supplied.

Sound to me to be really good people. Likely, I'll
order my rebuild stuff through them. I think, also,
twenty years of selling these parts, if I'm not mistaken.
 
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