TR4/4A Engine Question: The Valve Lifters

[KVH]

I have a very good spare set of used valve lifters. I don't see any hint of cupping.

While replacing my rings, however (long story), I noticed that two of my current lifters in use have some abrasions and chipping on the underside. One sort of bad. What causes that? I did run low on oil once.

Those lifters (the ones now in my car) all have a little oiling hole in the side. But if I replace the two chipped lifters with ones from my spare kit, they won't match since my spare set has no hole in the side of the lifter for oil. Other than that, they appear almost identical. Bright shiny steel.

Do I dare mix and match like this and put two of my spares in there, or do I just need a new set (and what about weight disparities)?

thx

 

[M_Pied_Lourd]

I'm no expert, but if I were going to use your good used ones, I would replace all the current ones, not just the two. I think I'd like to know more about what was going on with the two chipped lifters though...

What type of oil do you run? Just curious.

Cheers
Tush

 

[KVH]

. . . . I think I'd like to know more about what was going on with the two chipped lifters though... What type of oil do you run? Just curious. Cheers
Tush

One way or another, someone keeps getting it out of me. I ran the car more than two quarts low. You know, that lubrication stuff. But I was quick to react--once I heard the knocking. Could that be it? Seriously, I don't think the cam is damaged, and all the other lifters look good. I was using good heavy zinc laden oil. (ZDDP)

 

[CJD]

Lifters and cam lobes wear in together. Every shop manual tells you to keep them with the lobe they were with. I have always either kept them together or replaced them together.

In an optimum world, the lifters start with a slight dome shape, not perceptible to the eye. The cam lobe has an angle on it, so it imparts a twisting load to the lifter, causing it to spin...and also places a load on the cam to the rear of the block, so the cam does not tend to walk forward into the timing cover.

So...most lifters spin, and thereby live a long and happy life. Some lifters, for one reason or another, do not spin. They then start to wear a unique groove on the lifter face. This is not optimum, but will still run that way for many thousands of miles with no trouble. Now comes the rub...

Once a lifter is run for a while, the dome wears off, and the lobe and lifter are mated for the widest contact patch possible. No other lobe and lifter pair will have that identical wear pattern. If you slip a new lifter onto a used cam lobe...they may or may not re-mate before the hardened surface of the lobe is worn off. If you have a grooved lifter...it can only be replaced on the mated lobe, and at the same identical orientation it wore into. Both of these are "make it work in a bind" techniques.

In general, if you are concerned about the wear patterns on the lifters, then replace the cam and lifters with new. Second option...have the cam and lifters re-ground (about $60 total)...assuming you have a decent cam shop locally that can re-heat treat the surfaces properly. Mixing used lifters on a used cam is a big no-no. Final option is to put new lifters on a used cam...and cross your fingers. If it mates, you are good to go for many thousands of miles. If it doesn't mate...then the lobe will grind down within a thousand miles or so. Try to think about where all that ground lobe metal goes...and you'll see why I don't like to risk mixing new and used cam parts.

 

[Brit car fan]

Nah!! What you need is a set of high velocity bonkaminium alloy valve lifters like this!!


To go with the high velocity bonkaminium pistons like this!! (rings found in the sump) Acceleration = engine to sump in 6.8 seconds!!

Yahoo!!:excitement:

Seriously though it's not worth scrimping on valve lifters, whether case hardened, nitrided or chilled iron, if in doubt get new ones. I recently bought a set of eight on ebay for £21 including the postage. Whether you replace the camshaft or not is a question of purpose and finances. My Spitfire 1500's not out to win races, rallies or tour Europe. If it runs sweet enough and I can go for a nice drive in the country that's good enough for me.
Examine the lobes under a glass. Look for flats and surface break-down. Measure with micrometer the heights of the lobes from the heels to the tops of the cams, they should all be within a few thou, better still mount it between centres and check the rise with a clock.


I'm not a great believer in the 'always replace with new' religion, having had my share of shocks with after market parts I prefer to put my trust in the original parts where possible. Big car manufacturers and big names in the racing and rallying world can afford to have a no expenses spared approach but for us hobbyist bods in our garages we need to keep both feet on the ground if the cost of an engine refurb is not to spiral out of all proportion.

I shall await the barrage of abuse - my tin hat is firmly in place!!
Dave

 

[Brinkerhoff]

As a rule you aren't supposed to re use old lifters unless they go to the exact lobe they were worn in on. We aren't talking about a high performance engine though , and you will be using oil that far surpasses what was used originally, you may be ok .

 

[ghawk16]

So if I got a new 270 cam and the shop that has my lifters now grinds them down should I be OK or should I just save the hassle and get new ones to be safe? I was looking at the BPNW Hardened Tappets? Needed? Thanks

 

[TomMull]

As a rule you aren't supposed to re use old lifters unless they go to the exact lobe they were worn in on. We aren't talking about a high performance engine though , and you will be using oil that far surpasses what was used originally, you may be ok .

I am aware of that rule but I have not followed it and had no issues. I know that lifters and cams have been problematic with modern oils, so in that light, perhaps now is a good time to do it. You might also want to search this forum for cam and lifter "run in" also.
Tom

 

[TR3driver]

There has been a lot of troubles reported with new TR2-4 lifters over the past few decades; apparently no one uses the original "chilled iron" process any more (or doesn't do it right) and new lifters tend to either be too soft, or have too thin a hardened layer. The result can be spalling on the bottom (which is likely the "chipped" appearance that KVH mentioned). Apparently the problem is erratic as well; Greg Solow (The Engine Room) reported that he 100% tests all new lifters for hardness and always finds one or two in every set that aren't hard enough. Since the drain hole is an aftermarket trick, I'd guess that's what happened to KVH as well (meaning only some weren't hard enough).

From what I've heard, the ones from BPNW are hard enough, but have a chamfer on the bottom that may cause problems with some aggressive cams. Larry Young said the chamfer must be removed for use with his cams.

If you do reuse old lifters with a new cam, they should be refaced (ground) and surface treated. Any cam grinder should be able to handle that for you. It's been a lot of years back, but ISTR Babe Erson charged me less than $20 or so for a whole set. I actually asked him if it was per lifter, since I had expected to pay a lot more. The grind is not totally flat, there is a very gentle radius (something like 100") so I'd make sure to get an experienced cam shop that knows about it (and has the machine to do it).

Personally I wouldn't worry about the difference in weight. But the consensus seems to be that the drain holes don't add any performance (the oil gets bounced out in operation anyway) and weaken the lifter, so I might be tempted to go with the other set anyway.

 

[ghawk16]

Great! Thanks for the feedback Randall! This shop seems to know what they are doing and have done quite a few British engines. He said my lifters looked good, but since I'm putting in a new cam I have to at least grind them down. But I'll mention the surface treating to them as well and see what they say.