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Lifter failure?

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darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
Got some time to tear the engine down a bit more. Here is the cam and lifters, to me, just the failed one is the only one that looks bad.

There was some gritty junk in the pan, so I think I am going to strip out the crank and pistons, and give it a good cleaning. I was hoping to leave the pistons in, but I think giving everything a good clean is probably called for. I assume as long as I'm putting the same piston back in the same cylinder (which I need to do anyway) that I don't have to worry about anything like honing the cylinders?

I also found these two mystery pieces in the pan. The kind of look like timing chain rollers, but the size is wrong, and I don't see any damage to the chain. The best I can come up with is that the are part of the ring that is in the holes of the rubber valve cover gasket. I don't see any missing, but I have changed them once or twice since the rebuild, so I suppose one could have dropped in. Any other ideas on what they might have come from?



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

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POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
Do those two pieces look as though they were once just a single piece? It's just so strange to me that the rest of your cam and lifters looks perfect. Just seems unlikely to me that a single lifter could fail like that wiping out the cam or visa-versa. I'd really want to know were those bits came from.

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
In reply to # 1494454 by POW Do those two pieces look as though they were once just a single piece? It's just so strange to me that the rest of your cam and lifters looks perfect. Just seems unlikely to me that a single lifter could fail like that wiping out the cam or visa-versa. I'd really want to know were those bits came from.

The two pieces look like they could have been part of a single piece, but not all of it. Here is what I suspect they are piece of, the height is right, the material is right, and the curve on one part matches. The other looks like it was bent, but still matches up.

So my working theory is that one of these fell into the engine, and initiated the process of the lifter and lobe self-destructing. So far the only visible damage is that lifter and lobe, but I'll be sure to look very closely!



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

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POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
I see the similarity, and that is a spacer used in a rubber valve cover gasket?

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
In reply to # 1494494 by POW I see the similarity, and that is a spacer used in a rubber valve cover gasket?

Yes. There appears to be at least two styles of the spacers, this is one that appears to be aluminum. The new set of gaskets I have use a much heavier, cad-plated steel one. Those fit very snuggly in the gasket.



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
OK, I'm in a bit of a quandary. I have everything removed from the block except the crank and pistons. I was thinking that I should clean the block well, to make sure there isn't any swarf stuck inside. And I was thinking I might just replace the main and rod bearings as well. I initially thought I would be replacing the rear main seal, but that is all good.

But I've been reading stuff on the internet, and while there isn't a consensus, there majority think that if I remove a main or rod cap, then I have to replace the bearing since it won't go back in exactly the same spot, and will start a new break in. The majority opinion is also that if I remove a piston, that I need new rings and will need to hone the cylinder.

I have considered pulling the crank, but leaving the pistons in, but I'm worried that might be problematic, dealing with all of the rods. I know I can change the bearings without removing the crank (or rods), as I did that (from under the car) once before.

However, looking at the cam and lifters (other than the bad one), they all look really good. Though they are two hard surfaces, rather than a soft bearing. I have not opened up the oil pump, which would have been the most affected by any debris, since it sees unfiltered oil. But assuming that looks OK, is there much risk that the rest of the engine is full of swarf?

If I do decide to pull the pistons and install new rings, what size do I get? The stock bore is 3.5", and it was bored 0.020 over, so would I order 3.520? rings? I've always got rings with pistons. I found these on Summit, would they work?

https://www.summitracing.com/parts/mah-41118020/overview/

Or should I just clean what I can and start putting it back together?

-Darrell



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
I've heard the 'facts' from both camps, My own feelings that a light hone just to re-introduce a crosshatch is disable with new rings. When I did mine at 58,000 the stock bore measured on taper so I used a Flex Hone. At the present 71,000 there is absolutely no smoke. What I've heard about bearings is the built in interference or crush with original install is lost and there is a chance a bearing could move around in it's saddle or even spin if re-installed. If this is true it may be more likely on high dollar really stressed racing engines rather than our streeters.

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darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
So I'm looking at the Flex-Hones. They say:

Quote: Tool diameter is determined by the nominal bore size in which the tool is to operate. e Flex-Hone Tool is always produced and used in an oversize condition. The degree of oversize creates a soft cutting action. For example, a 1” Flex-Hone size is ordered if a 1” bore is to be finished and the tool is provided oversized. If the bore size is between standard Flex-Hone sizes, the next larger standard Flex-Hone should be selected. For instance, if the nominal bore is 1.093”, then the 1-1⁄8 ” Flex-Hone is ordered.

They have a 3.5" and a 3.75". For for my 3.520" bore, would I need the 3.75" hone?

What grit should I use? 240?

Any thoughts on the Mahle rings?

Am I crazy to consider honing the bores myself?



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA



Edited 1 time(s). Last edit at 2017-10-29 09:21 AM by darrellwalker.

POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
Just looked at my Flex-Hone®, The one I used on my standard bore. It is GB31224 and has a grit rating of 240. As I recall, the Flex-Hone® web site recommended various grits according ring material and bore/liner material too. I used cast iron rings (no chrome plated top ring) and 240 grit is what was recommended. Physically measuring it just now shows it to be in the range of + 1/8", That's .125" inch over so with a + bore of just .020" it is well within the range of perfect. Using it is quite easy, almost too easy as there could be a tendency to overdo it. I used a variable speed electric drill. Before you pull the trigger get the hone into the bore. I used WD-40 as a light lube so the stones won't pack up.Use a medium speed and as the hone turns work the drill in 'n out, in 'n out 7 or 8 times. You don't want to oversize your bore so in 'n out a minimum of strokes. At the last up stroke release the trigger and withdraw the hone at the same time. Look at the bore to make sure there is no glaze left. Seven or eight strokes aught to do it, and you will be amazed at the perfect cross hatch created.
I don't have any practical experience with Mahle rings but they've been around for a while. I would do a little research about cast iron rings as apposed to chrome rings though. My understanding is that chrome top rings are very durable and have been used for ages in new, from the factory, engines. They are OEM in our 3.5's. Generally speaking though the factory finished bores are absolutely perfect in every conceivable way with a bore finish that is hard to duplicate. In a sense, perfect chrome rings are running in perfect bores and so break-in is not so much of a thing. Cast rings on the other hand are generally what's used in rebuilds because they are more tolerant of a bore's finish. The rings are breaking in and mating with the walls and at the same time the walls are getting to know the rings.

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darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
Hi Peter, thanks for the thoughts.

I pulled the oil pump apart, and I think there are a few new scratches inside, but nothing too bad. But there appears to be some wear in the bottom of the cam bearings (they were replaced the the rebuild). So I've decided I'll pull the crank and pistons, and have the machine shop replace the cam bearings, hone the cylinders and clean the block.

I'm not finding a lot of choice in rings. I can order some from Egge, where my pistons came from, they will supply Grant rings (at leas last time). RockAuto had some Total Circle rings, but nothing in 20 over. So I may go with the Mahle rings.

-Darrell



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
Egge pistons are what TSI in Ohio supplied along with Grant rings I believe. They have proven fine with no oil use in around 14,000 mi. There was no oil consumption with the previous pistons/rings either, the rebuild was strictly to freshen the heads and raise compression.

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
Took the pistons and crank out. Some scuffing on the bearings, and a few larger scratches. Crank journals look fine. These have less than 5K miles on them.



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA


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Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, Oregon, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1494931 by darrellwalker Took the pistons and crank out. Some scuffing on the bearings, and a few larger scratches. Crank journals look fine. These have less than 5K miles on them.

Darrell:

Hard to tell from the photo, but I do not see anything wrong with those. I don't see the copper backing showing anywhere.

If you run your thumbnail back and forth across the bearings, and it does not snag on anything, the bearings are pristine. Your thumbnail makes a remarkably sensitive profilometer.

Same goes for the crank journals. Your thumbnail will tell you if anything needs to be cleaned up.

Mahle is a reputable ring maker, so no worries there. Ductile iron rings are plenty good for the street. They will bed in quickly and are long wearing. I used Hastings on my car, another good supplier.

Vance



1980 Platinum Metallic TR8, navy blue interior
Bare metal respray, Crower cam, raised compression
ported heads, modified Zenith carbs, 0.060" overbore

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
Hi Vance,

Certainly no copper showing. Here is a closer picture. The bearing on the right (a main bearing) has a shiny area, but nothing that can be felt. But the two rod bearings on the left have a long streak, and you can feel those. But I don't feel any corresponding scratches in the crank. But I think I'll take it along to the machine shop to get their opinion.

-Darrell



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA


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darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
BTW, speaking of exposed copper, here were the original bearings.



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA


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