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Boring Cylinders or Inserts

Hegg

Jedi Hopeful
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Since the TR7 has the cylinder sleeve inserts for the block, would it generally make more sense to replace those instead of reboring, or is it best to go for the rebore and get oversized pistons/rings?

Just wondering...
 
I'm not at all sure that the 7 is a sleeved engine. My first guess is that it is not. I have heard of several engines rebuilt with oversize pistons including 2 of my own. My current daily driver was rebuilt with 2nd O.S. pistons 14,700 miles ago. In theory the cylinders can be rebored with the engine in the car. I don't know of any that have been done that way, but the engine is supposed to be rebuildable, except for the crank, without pulling the engine. Getting the head off, without destroying it, is usually the biggest bug a boo. I put new main and rod bearings in mine in my driveway, but the crank was too far gone for this to be a good repair, hence the rebuild with a new crank.
 
The cylinders are lined, but you can bore them out to +40 oversize before you need new liners. The liners themselves are not overly expensive, but it would cost far more to have them installed then to just bore an oversize, since the new liners would need to be bored anyway.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Mark Beiser:
The cylinders are lined, but you can bore them out to +40 oversize before you need new liners. The liners themselves are not overly expensive, but it would cost far more to have them installed then to just bore an oversize, since the new liners would need to be bored anyway.<hr></blockquote>

Aaah, I see. I figured it would be sorta tough and painful to pop the liners anyhow. But it's good to know that most of the work can be done with the motor in the car.

Thanks!
 
Hi Guys,

You can do anything to a block with it in except for vating. As for taking the heads off you just have to pay attention. Benn rebuilding engines since I was five and whenever I am doing one that doens't need to be vated I just do an in frame major.

Cheers,
thirsty.gif
driving.gif

Walter
 
Sorry if I sound dumb, but what's "vated"?
 
Hegg,

No such thing as a stupid question. Vating a block is when you take it into a machine shop and the block is submerged in a large vat of lye to clean it. Very effective but you always have to replace the cam bearing when you do it.

Cheers,
thirsty.gif
driving.gif

Walter
 
Aaaah, ok. I've just always called it "boiling".

Thanks!
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Hegg:
Aaaah, ok. I've just always called it "boiling".
Thanks!
<hr></blockquote>
Also called hot tanking & a few other things. A very good thing to do to your engine if it has a lot of age or miles. The improvement in cooling can be very noticeable. Only boil ferrous materials in caustic. Bearings, aluminum, & such will be dissolved.

There are acid tanks for cleaning aluminum.
D

[ 02-19-2004: Message edited by: Dave Russell ]</p>
 
confused.gif
So who sells bore liners for a TR7? I have seen the part numbers in the catalogues from Triumph, but never held one in my hand, was told that they never had any demand for them.
cheers.gif
 
Glenn, Victoria British has them listed, P/N 1-170.
Any good automotive machine shop should be able to cross reference and source them, as well.
Jeff
 
So now I was all excited to leave my motor in the car while I do some rebuild work on it, but then I remembered the whole reason I was going to pull it was to replace the clutch (it's going out I think), and thought since I pulled the engine for the clutch I might as well rebuild it while it's out.

So... can I replace the clutch easily without pulling the whole engine out? Is there enough clearance?

And would it be a good idea to boil the block anyway? The motor has around 90k on it (I think -- speedo is broke). I just tested compression tonight and had between 105-115 in all cylinders. Is that pretty decent for being at 4200 feet?
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Dale:
I don't know of any that have been done that way, but the engine is supposed to be rebuildable, except for the crank, without pulling the engine. Getting the head off, without destroying it, is usually the biggest bug a boo. I put new main and rod bearings in mine in my driveway, but the crank was too far gone for this to be a good repair, hence the rebuild with a new crank.<hr></blockquote>

I was just getting ready to remove the head... then I re-read your statement here. What should I be cautious of? Any tips are greatly appreciated!
 
Hegg,

Not sure this method will work on a TR7, but I have done it many times on American cars with plenty of room. You can get a few long grade 8 bolts say four and use them to replcae four of your tranny mounting bolts. Then you can remove the rest of the tranny bolts and slide it back on the long ones. then you can just break the pressure plate loose let the clutch drop out and replace it. Usually takes about two hours to do. But like I said not sure it will work with a seven because I am not sure there is enough room to even consider doing it.

Cheers,
thirsty.gif
driving.gif

Walter
 
Hegg,
Sorry to be so slow in getting back to this thread. The first TR7 head I removed had run only a short time before being wrecked and then sat for 13 years. It came off easily without removing 2 of the 4 slanted studs. The head on the engine I had rebuilt had to be destroyed to get it off. I thought I was in good shape with the other to use but it was warped badly and not repaired properly. Warped heads are common on these engines, and removal is a pain due to a number of things. The end result if done properly is worth it. I have 15,000 miles on mine since the rebuild and drive it daily. It is a sweet running engine and I'm very proud of it even though I farmed out the actual rebuild of the block and head. Good Luck and stay in touch. There are a number of members of this forum that have considerable experience with the 7 and could write the book. A search of this site would yield a lot of threads and posts.
 
Hegg,

If you were just going to redo the clutch, the transmission is removable by itself, ( pretty easily also ). However, If it were mine and I was even considering a rebuild on the engine, I would yank the engine and trans together, ( only way to get the engine out ).
 
iagree.gif
That's right. Trans will come out the bottom with the bell hsg. But the engine won't come out the top without the trans.
 
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