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MG MGA - Quality parts ?

I just pulled the head on my 62 MK-II, with a stock 1622 engine to change valve seals from stock, to unbrella type.I rebuilt the engine only 10,000 miles ago. Bored .020, new cam and lifters, and all the rest that go with a rebuild. I used a good assembly lube on the cam and lifters. I pulled the lifters to check them, and several have large chunks of metal missing from the bottom. I will have to pull the cam to check it out also. I rejected the first lifters that I purchased for the rebuild, (rough surface on the bottom), and bought another set from the east coast that looked good on the bottom. Now where do I go to get GOOD QUALITY PARTS? Lifters should not go bad in 10,000 miles. Has anyone found a source of quality parts? Help!!!!
Ed Bell

Hi Ed. What do you mean by large chunks of metal missing? Does this mean chunks broken off from the circumference of the lifter bottoms, or does it mean deep wear/pitting on the lifter bottom. Did you use moly based assembly lube on the lifters before engine assembly? Non moly based lube DOES NOT provide adequate protection for the lifters and camshaft lobes! These parts are under extreme pressure, and require moly based assembly lube to survive the initial engine startup and wear in process, according to the Crane Cam website. Right after the engine was started, did you check to see that all the pushrods were spinning? The cam lobes are ground so that the lifters (and therefore pushrods) spin to prevent excessive wear. If the lifters do not begin to spin spin, wear on the lifter bottoms will occur (even with moly lube). Should a pushrod (and lifter) NOT start to spin on the initial engine start, the pushrod should be spun manually, with the fingers, until the pushrod and lifter keep spinning without assistance. As for where one obtains quality parts, perhaps yours were quality parts, but simply had inadequate lubrication to start with, or the lifters were not spinning as required? Or perhaps your lifters were poor quality steel or improperly hardened? Personally, I don't know who consistently sells high quality parts. I installed new lifters from Moss during my rebuild last winter. Unfortunately, I have no idea how well or how poorly they are holding up. I did however use moly assembly lube, and did ensure that all pushrods were spinning. Cheers! Glenn
Glenn

Glenn,

How exactly do you look for the spinning? By running the engine with the valve cover off? If so, how much oil is sprayed around?

- Ken
Ken Doris

Hi Ken. Yes, I left the valve cover off to visually verify the pushrods were spinning. Yes, oil squirts everywhere, and makes a real mess. Unfortunately, pushrods (and therefore lifters) that do not spin, create even bigger headaches. The non rotating lifters suffer extreme and rapid wear, along with the camshaft lobes! So having to mop up an oily mess is only a minor annoyance in comparison. For someone more innovative than myself, it would likely be possible to cut part of the top off of an old valve cover just enough to see the pushrods. Alternately, one could make a pseudo and temporary "valve cover" from sheet metal, plastic, or perhaps even waxed cardboard. Cleaning the slopped oil took me about an hour and a half, but that was using a spray can of degreaser and paper towels. There are likely quicker ways to do this chore. Cheers! Glenn
Glenn

Glenn, the lifter in question had a crater in the center of it about 1/4 inch in diameter. It looks like the hard surface broke away from the base metal of the lifter. There were two otheres that showed small pitts on the bottom, but had not lost large pieces. I have rebuilt Cheverolet, Ford, and Chrysler engines without any problem in the past. When I assemble an engine, I expect to get many miles/years of use out of it. The engine in my MGA had 100,000 miles on it. I expected to be able to put another 100,000 on it after the rebuild.
Ed Bell

Ed,
All your lifters should have convex bottoms. This is what causes rotating of the lifter. The cam lobes are flat edge to edge. If you had a smooth concave crater, or the bottoms are flat, this would indicate that your lifter was not rotating. The hardening is not supposed to be welded to the lifter, but supposed to be an integral part of the lifter, i.e. the lifter should have been manufactured and then the bottom should be hardened. It sounds as if your hardened surface fractured off, which could indeed come from lack of lubricant during start up, or weld hardening. Do you have any blueing of the remaining lifter surface? Also, how does your camshaft look. ( no doubt ruined from the bad lifter) Does it look as if the camshaft failed, causing the lifter to fail? If the hardening came loose from the lifter, can you peel any more away? (I ask this to ascertain whether suppliers are weld hardening the lifters.)
mike parker

This is the first I have heard of cam followers spinning. How is it achieved? Mike, simply having a covex bottom won't cause spinning. There has to be some force off centre to the follower axis. Are the cams off centre?
Art

The cam lobes have a slight taper to induce the rotation. Bad repro cam followers are a serious problem. There was an extensive thread on this on the TD board a few months ago - something like "rapid cam follower wear on Crane cams" Moss jumped in and said they are aware of this and are taking steps to rectify, one hopes that they will extend this to all their followers.
FRM
http://www.usachoice.net/gofanu
FR Millmore

It might be worth reading Doug Jackson's technical brief on camshaft selection (MGB 20). He definitely does not recommend Crane cams due to the lifter wear problems his shop has experienced.

http://www.mgbmga.com/tech/mgb20.htm

Steve
Steve Brandt

Art,
You are correct in that the followers must be off center. Check out the lifter alignment, and you will see them slightly off center with the camshaft lobe.
mike parker

I'm in possession of a new Crane cam and, quite frankly, am very nervous about installing it after the various problem reports I've heard or read about. I contacted both Moss and Crane about these concerns and got no response. Another new part for the scrap heap?
Thanks,
GTF
G T Foster

Hi GT. I certainly understand your concerns! I think I would probably hold off on installing the new camshaft until you are able to get assurances from the manufacturer and/or vendor that parts quality is guaranteed. I would get such statements IN WRITING. If either or both parties continue to refuse to respond, or refuse to give a written warranty or assurances regarding a promise to accept defective parts back for a full refund, I would recommend returning the uninstalled camshaft, and then purchase one from a vendor/manufacturer that has rock solid reputation and warranty. It is extremely upsetting to install defective parts, and then have to repair the damage, and also have to fight with the manufacturer/vendor to put things right. Been there, done that! Just my 2 cents worth, Glenn
Glenn

Might also want to look at Chilled iron lifters from APT (no connection). The use an cooling plate in the mold near the lifter casting to keep the grain size of the lifter snaller. Supposed to result in a harder but better wearing lifter face
greg fast

GTF and Steve:

Doug Jackson may have his own recomendations, but his is just one opinion. Copied from his site:



>>Our earlier recommendation Moss part 222-270 dual pattern (Crane part 342-0010) did not perform as forecasted. So, subsequently we no longer install this camshaft.


We were unaware at the time that the camshaft lobe material required a lifter with a minimum hardness Rockwell RC scale of 60. Iskenderian was the only company making such a lifter (part SP-002). Unfortunately, they have been discontinued for many years. Consequently, using this camshaft with lifters less than 60RC will result in lifter failure. <<

I hate to disagree with Doug, but this argument does not make a case against the Crane cam. Crane has been making new billet cams for the B series for many years and literally many hundreds of these cams have been installed with no problems.
Crane produces a very high quality product that has not had any documented quality issues in the entire time it has been carried, which is why Moss and I personally recomend it. Lifter failure is typically caused by two problems. Poor quality lifters and incorrect assembly.

Greg: All of the B series tappets are made from chilled cast iron. The problem is that the batches have intermittant quality control and surface hardness can be variable. This has not been so much a problem with the MGA/early B long lifter but has been a major issue with the later short bucket design. Currently the only way that Moss can stand behind the short bucket lifter is to ship every single one of them out for hardness and dimension checking. This is expensive, but the only way to ensure that they are not going to contribute to an engine problem.

Glen: You hit the nail on the head. The lifters must be rotating when the engine first fires. If they don't they will fail prematurely. From the research I've done, many tappet failures initiate in the first 15 minutes of running.

Unfortunately the high loadings on the B series tappet faces mean that they are critical to the life of the engine.
Finding a supplier of consistantly good tappets is a problem that we are all facing. It's nothing new, as British Leyland had problems with the short bucket lifters when they came out. From my experience, you were lucky to get 40,000 miles out of a set.

Kelvin.
KJ Dodd

So Kelvin, where does that leave us? Is Moss now supplying short lifters that it (you) guarantee that, if installed properly, will have a normal (e.g. 100K) lifetime under "normal" (non-racing)operating conditions? I have one of your superchargers and after reading Doug's technical brief I have been conflicted as to what cam/lifter combination to use when I assemble the engine. The Crane cam has good specs, but the last thing that anyone wants is to tear down an engine for premature component failure. Any opinions on the Kent lifters? Recommendations?

Steve
Steve Brandt

Kelvin:

In the previous post, I should have also you asked why, again according to Doug Jackson, the lifter failure phenomenologically seems to favor Crane cams and not be as much of a problem with the Elgin cams he now uses and recommends? I'm sure Moss'statistics include all installations using both long and short versions of the B-series lifters and Doug prefers to assemble his engines with only the short (later) style so his experience is more item specific and focused on racing.

Steve
Steve Brandt

Steve:

I'd suggest getting the actual information from Doug, but I was not under the impression that he had "phenomenological" problems with the Crane cams, just a poor experience with one. Sorry, I'm an engineer, English never was my strong suit.
Elgin has nothing bad to say about the Crane cams, so I'll leave it at that.

Where it leaves us, is very confused. I've got a Tech guy that used to race MGAs who swapped cams and lifters on a regular basis and never had any problems. I had a 65B engine with 118,000 miles that had 3 pitted lifters. I put 3 good used ones in and continued to run for another 50,000 miles. Yet at this time, every single lifter that comes into this building is suspect. I've got a British automotive engineering paper that states anything with a surface hardness greater than 45 Rc is likely to spall under load. But I have race engine builders who won't use anything under 55 Rc. Crane suggests that lifters of minimum 60 Rc be used on their cams, but guess what, no one makes them. If anyone can come up with some serious documented design evidence I'd love to hear from them directly. I've talked to some of the National Automotive Societies, but if it doesn't have an overhead cam, they don't know what to do.

The basics are: Buy a cam from a reputable manufacturer or grinder. Crane, Kent, APT, Elgin etc.

Have all lifters checked dimensionally and for surface hardness. My recomendation is 45-55 Rc. Make sure the lifter bores are clean and that valve spring height and rocker arm geometry are correct. Ensure that the lifters are rotating when the engine is fired up. Keep an eye on valve adjustments.

I'll know more when I pull the lifter set out of my car.

Kelvin.

KJ Dodd

FRM,
I was not aware of a taper on the cam lobes. I have always thought that they were totally flat on the lobe. Is there a visible taper, or do you require a dial indicator to see it?
mike parker

Hi Mike. You are correct. While the cam lobes look flat, they are indeed ground to incorporate an almost imperceptible taper. Cheers! Glenn
Glenn

This thread was discussed between 05/12/2004 and 09/12/2004

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