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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"
So my TR8 has had some valve train noise for a while, I finally decided to investigate. I found that there was significant slop between one of the rockers and an intake valve. I initially suspected something with the rocker, and indeed it was beat up where the pushrod was bouncing around. But the hardened seat still seemed to be in place, and swapping in another rocker still has the same problem. I checked the pushrod, and it hadn't magically shrunk. As best as I can see, it looks like the seat in the lifter is up against the retaining clip, but it is hard to tell for sure with the intake and head in place. The lifter does go up and down, but the valve is barely opening. In any case, I wouldn't expect the base circle of the cam to wear away that much, so it still looks like a lifter issue.

So I'm going to have to pull the intake and take a closer look. If I do need to replace the lifter, does anyone have a part number? Any other theories on what the problem might be?

Edit: Is the correct part number for a new lifter? Sealed Power HT896



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



Edited 2 time(s). Last edit at 2017-10-11 12:16 PM by darrellwalker.

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Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, Oregon, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1491385 by darrellwalker So my TR8 has had some valve train noise for a while, I finally decided to investigate. I found that there was significant slop between one of the rockers and an intake valve. I initially suspected something with the rocker, and indeed it was beat up where the pushrod was bouncing around. But the hardened seat still seemed to be in place, and swapping in another rocker still has the same problem. I checked the pushrod, and it hadn't magically shrunk. As best as I can see, it looks like the seat in the lifter is up against the retaining clip, but it is hard to tell for sure with the intake and head in place. The lifter does go up and down, but the valve is barely opening. In any case, I wouldn't expect the base circle of the cam to wear away that much, so it still looks like a lifter issue.

So I'm going to have to pull the intake and take a closer look. If I do need to replace the lifter, does anyone have a part number? Any other theories on what the problem might be?

Edit: Is the correct part number for a new lifter? Sealed Power HT896

Darrell:

More likely you lost a cam lobe. Even if it was the lifter that failed in the first place, it would have hammered the cam lobe in a short time. You should plan on replacing the cam and all the lifters. Your existing lifters cannot be reused with a new cam, or you will be replacing the cam again in 500 miles or less. You have lost a significant amount of power and economy as a result of the failure, so it is very much worth fixing.

I can recommend the Crower Cams as they are a modern design, with the exhaust duration being longer than the intake and around 60 degrees difference between the advertised and 0.050" duration. Some are 80 degrees difference or more, and will not perform well.

Losing a cam in the Rover V8 is a relatively common occurrence, at least on high mileage engines. Also, if the cam was ever replaced and not broken in properly a lobe failure is all but inevitable.

You need not remove the heads for a camshaft replacement, but you will need to remove the intake manifold, rockers, radiator, water pump, and front engine cover.

I used Comp Cam lifters in my engine rebuild. They still make their own lifters, and they are top quality. They do not list the Rover/Buick 215 V8 in their catalog, but the same lifters were used in Cadillac motors from the early 60s and the Buick 350 V8, and those are listed (Part no. 869-16).

I you will also need to replace the timing set along with the cam.

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,

Thanks for the reply. Cam and lifters were replaced and properly broken in when I rebuilt the engine a couple of years ago. Doesn't mean that isn't the problem, though. Oddly enough, it was running really well.

If I do need to swap the cam, I currently have an Erson TQ20. What would you recommend as a similar performance cam from Crower? The spec sheet for the TQ20 is attached. I do have larger valves installed in my heads, headers, and an Edelbrock Performer manifold.

-Darrell



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

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Attachments:
NewCamSpec.pdf    783.3 KB

TR8todd Avatar
TR8todd Todd Kishbach
Mass, USA   USA
1977 Triumph TR7 "Rally Fraud"
1978 Triumph TR8
1979 Triumph TR7
1980 Triumph TR8    & more
Sounds like a cam lobe to me. About 8 years or so ago there was a bad batch of cams that came thru. They were not hardened properly and some wiped out lobes very quickly. Of course everybody selling the cams denied it, but I personally know of two people that sent there bad cams out to be tested, and sure enough, they were not hardened properly. There was a 6 month period or so where the vendors knew the cams were bad, but kept on selling them. Some even posted "how to properly break in your cam" threads on their website. Plausible deniability at its finest. Make excuses instead of making things right. FWIW, I haven't wiped out a cam since I started running ZDDPlus in my oil.

Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, Oregon, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1491406 by darrellwalker Hi Vance,

Thanks for the reply. Cam and lifters were replaced and properly broken in when I rebuilt the engine a couple of years ago. Doesn't mean that isn't the problem, though. Oddly enough, it was running really well.

If I do need to swap the cam, I currently have an Erson TQ20. What would you recommend as a similar performance cam from Crower? The spec sheet for the TQ20 is attached. I do have larger valves installed in my heads, headers, and an Edelbrock Performer manifold.

-Darrell

Darrell:

Since you know the history of the engine, and the cam is only a couple of years old, I am a good deal less certain about my diagnosis. Obviously you will need to at least remove the intake manifold, so you can determine the true cause. BTW, I must ask - did you have your valve guides machined down for the Erson cam? You are past the absolute upper limit for that amount of valve lift. Anything past 0.450" valve lift must have the keeper to guide clearance checked and will probably need the valve guides cut down, since your lift is 0.0478". If you did not have your valve guides cut down, that may be why your valve train is acting up. The valve keeper will crash into the valve guide, and overload the lifter and cam lobe causing a failure. If this is not what happened and your valve guides were not cut down, you are very lucky indeed. I hope you also are running suitable springs, or at least verified that the stock springs do not stack solid with that much lift - that is another way the camshaft can destroy your lifters. I guess I am saying you should check both of these measurements if you did not when you put in the cam.

For the sake of argument, let's say that you find the cam needs to be replaced. The Erson cam is an old school cam. I am sure it works well, but you can do better with a more modern design. A 78 degree difference between advertised and 0.050" duration indicate that it is a late 60s design, with lazy opening and closing ramps. State of the art for the 60s, but not what you want now.

What do you want most from a cam? Do you want that bad boy idle, or are you wanting street drivability? I ask because you can have the same power with a better idle and better fuel economy, or more power with the same idle, or somewhere in between.

With 109 LSA and 214 duration at 0.050" you are definitely into the potato-potato-potato idle territory. Some people love it, I find it tiring after the first 2 weeks. sad smiley

For an equivalent power cam Crower part number 50231 will get you the same power, but with noticeably better idle and economy (and for that matter, emissions too). Maximum lift is 0.477. For an equivalent 'bad boy' cam sound, 50233 will give you roughly the same amount of chop and more power than you get with your current cam. Maximum lift is 0.501. Both of these have roughly 60 degrees difference in advertised and 0.050" duration, so the valves are opening more rapidly - this improves economy, idle and emissions without sacrificing power. In either case, the heads WILL need to be machined if they have not been already. And you are definitely looking at aftermarket valves springs on the latter cam - stock springs will not handle that much lift. Both of these cams are available through Summit Racing for a good price.

The maximum cam you should use with stock valve guides and springs is part 50230. That has a lift of 0.451"

Let us know what you find.

Vance



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

TR8todd Avatar
TR8todd Todd Kishbach
Mass, USA   USA
1977 Triumph TR7 "Rally Fraud"
1978 Triumph TR8
1979 Triumph TR7
1980 Triumph TR8    & more
.470 is the absolute max on stock valve springs. Even at that lift, its a crap shoot whether or not they will snap after a few hundred miles. If you want more lift than .450 .460, as Vance has said, you will need Chevy valve springs and you will have to machine the valve pockets to get the proper installed height. Last quote I got to do the oversized valves, Chevy springs, port and valve job was $1000 and I had to supply the valves.

darrellwalker Darrell Walker
Vancouver, Washington, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
The head was reworked for large valves, and does not have stock springs. It was set up for the TQ20 cam, so it should be OK.

Intake will be coming off in the next few days, and then we'll know for sure.



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"
Hi Vance,

Thanks for the recommendations. I'm not too bothered by the current idle, but I have TBI system that may be taming it a bit. I'm happy with the current power, so the 50231 sounds like a good choice.

-Darrell



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"
Took the intake off. Lifter is toast. I assume the cam lobe is too, I haven't turned the engine to see how much of a bump is left.



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 # 1491572 by darrellwalker Took the intake off. Lifter is toast. I assume the cam lobe is too, I haven't turned the engine to see how much of a bump is left.

Yikes! May your lifter rest in peace...

Based on the tiny amount of the cam lobe that is visible in your photo, the cam is toast too. I say this because the entire width of the lobe is worn (shiny) so the lifter was riding on the edges of the lobe. The lobe will have a round cross section, which of course is bad mojo. sad smiley

So, you need to make sure that your machinist did everything correctly, so this will not be repeated.

1. Check coil to coil spacing on a valve spring at full valve lift. You need 0.010" spacing minimum between coils.
2. Check valve spring retainer to valve guide clearance at full lift. You need 0.060" minimum.
3. Check the affected valve stem to make sure it is not bent. If it is bent it will bind and hammer the new lifters/cam.
4. If the valve stem is straight, slide it into the affected valve guide. If should slide in smoothly, with no binding over any part of its travel.

If all of that checks out, then we need to review the cam break in process:

1. Generous amounts of cam break in lube on the lobes and lifters during reassembly.
2. The first time the engine fires, you must immediately take the RPMS up to 2,000 RPM for a minimum of 20 minutes.

The cam is oiled by 'splash' lubrication. 2,000 RPMs ensures there is a generous amount of oil being splashed on the cam lobes during the critical first few minutes of service.

Keep us posted.

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,

Thanks. Sounds like the heads are coming off, too. Any trick to measuring the clearances? I was going to turn the engine, but the lifters have already bleed down, so that won't work. I'm thinking I would put it in my press to move the valve, using a dial indicator to know how much to open the valve, then measure the clearances.

Break in was exactly as you describe, with the addition of pouring a bottle of ZDDP over the lifters/cam, priming the oil system with a drill and using 30wt non-detergent oil for the break in.

The lobe is indeed rounded over. Is it possible that the lifter was soft? Unless I find a problem with that valve, it seems that it would have to come down to that lobe on the cam or the lifter.

-Darrell



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

Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, Oregon, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1491431 by TR8todd .470 is the absolute max on stock valve springs. Even at that lift, its a crap shoot whether or not they will snap after a few hundred miles. If you want more lift than .450 .460, as Vance has said, you will need Chevy valve springs and you will have to machine the valve pockets to get the proper installed height. Last quote I got to do the oversized valves, Chevy springs, port and valve job was $1000 and I had to supply the valves.

Todd:

A total car fiend like you, I am surprised you are not porting your own heads. Perhaps your mechanic has a flow bench or years of experience that makes him a go to guy, but I have ported my own heads, and it is not difficult. Of course to get that last few percent of flow increase, you do need a flow bench and some other specialized tools.

Oh, wait. I forgot, you race. OK, then someone with a flow bench is definitely preferred.

Vance



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

TR8todd Avatar
TR8todd Todd Kishbach
Mass, USA   USA
1977 Triumph TR7 "Rally Fraud"
1978 Triumph TR8
1979 Triumph TR7
1980 Triumph TR8    & more
Racing has nothing to do with it. I'm good with just dropping off a greasy engine and coming back a week later to get a rebuilt one in a nice clean plastic bag. Maybe if I had the machines required to bore cylinders, line bore crank journals, machine valve pockets, etc. I would take a more active part in rebuilding them. Plus there's the whole time thing. With multiple TR8 projects going on, how I allocate my time is an issue. I've had the same machinist for 30 years. He has done hundreds of Rover V8s. I trust him, and everything he has ever done for me has come out perfect. Wish I could say the same for my own mechanical work.

Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, Oregon, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1491616 by darrellwalker Hi Vance,

Thanks. Sounds like the heads are coming off, too. Any trick to measuring the clearances? I was going to turn the engine, but the lifters have already bleed down, so that won't work. I'm thinking I would put it in my press to move the valve, using a dial indicator to know how much to open the valve, then measure the clearances.

Break in was exactly as you describe, with the addition of pouring a bottle of ZDDP over the lifters/cam, priming the oil system with a drill and using 30wt non-detergent oil for the break in.

The lobe is indeed rounded over. Is it possible that the lifter was soft? Unless I find a problem with that valve, it seems that it would have to come down to that lobe on the cam or the lifter.

-Darrell

I rotate the engine to maximum lift on a valve and then use feeler gauges to check the coil clearance. For the keeper to valve guide clearance, I do it with the head off the engine, and no valve spring installed. I use my dial caliper to measure the clearance with the valve closed, and then subtract the rated lift at the valve. You should have at least 0.060" left over, otherwise the Keeper can crash into the valve guide. With your current cam, you will not have enough room left unless the valve guides have been machined down.

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"
In reply to # 1491905 by Darth V8R
I rotate the engine to maximum lift on a valve and then use feeler gauges to check the coil clearance.

Hi Vance,

How do you deal with the lifter bleed down?

-Darrell



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

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