Swivel-Foot Valve Adjusters

[parmstrong]

I just got to the valve train portion of my AereoVee assembly and ran into an issue with the swivel- foot valve adjusters. I first spotted it when the ball (swivel-foot) on one adjuster would not rotate. I removed the adjuster from the rocker arm and found that one oil gallery/hole was obstructed (see photo in URL below), also there was manufacturing residue inside the stem of the adjuster. In this case the flat portion of the ball was facing into the cup and it seems that there were metal filings in the void created between the flat on the ball and the top of the cup which prevented it rotating.

It turned out that five out of eight adjusters had the “obstructed hole” problem, complete with metal cuttings inside the oil passage. Took a lot of patience to ream and clean them all out. Still considering purchase of a replacement set.

Thought I should mention here it in case the problem extends beyond my batch of adjusters.

[lutorm]

When I rebuilt our Aerovee this winter I ended up getting two different sets of those adjusters. The first ones were from EMPI and looked to be terrible quality, not only did the ball rotate feeling like it was full of sand, but the flat part of the ball looked like someone sawed it with a hack saw, full of ridges. I did not like the look of them one bit.

Fortunately I was saved from deciding whether they were too bad to be used when I realized our Aerovee had rocker arms with 9mm adjusters (apparently manufactured by CB for a short while a decade ago) so they didn't fit anyway. I ended up replacing the entire rocker assemblies with ones from SCAT. These adjusters were a lot better, but I still noted burrs in the holes that looked like what you have although not nearly as bad. They came off pretty easily when poked with a scribe and then I carefully back-flushed the passage from the ball side with mineral spirits and blew them out.

(Incidentally, when I disassembled the old rockers several of those passages were clogged with tiny RTV debris. Keep RTV far away from the engine when assembling it, especially if you run without an oil filter...)

[gammaxy]

I notice you haven't posted before, so you may be unfamiliar with some of the adjuster failures that have been discussed in the past. The only one I know of with an NTSB report happened to be installed different than shown in the instructions--lots of exposed threads and the oil passage not supported or able to transfer oil. Others have had similar failures and post frequently on the forum. I imagine they will say theirs were installed correctly, so there may be other possible failure modes at work. Personally, I'm careful to use a torque wrench every time I adjust mine. I'm sure you did the right thing by reaming and cleaning them out.
viewtopic.php?f=25&t=3688

Keep RTV far away from the engine when assembling it, especially if you run without an oil filter...

I think this is probably good advice, but it might be worth pointing out that the instructions have you use a light coat of red RTV when installing the oil seal. I caught a surprisingly long piece in my screen. Next time I do it, I'll be careful to re-evaluate my definition of "light coat".

[Area 51%]

I too noticed a very distinct "gravely" feel to the swivel balls, and quickly abandoned them in favor of a set of CB's. The supplied adjusters and rocker arms are unmistakably Empi units as identified by the color of the packaging. The warehouse for reasons unknown, but I could take an uneducated guess, remove the Empi name from the packaging. They are for sale if anyone wants to take a chance.

Page 23 of the Aerovee assembly manual deals with the installation of the rocker shafts and blocks. It states the slot on the blocks should be oriented in the down position. I have 3 different repair manuals (Bently, Clymer, and Chilton's) that all disagree with that orientation. They all say UP. As delivered fully assembled in the packaging from both CB and Empi, the slots are in the UP position. Is this a flaw in the assembly manual? or is there something I'm missing about the Aerovee?

[SonexN76ET]

My understanding from expert sources is that it does not matter whether the slots in the rocker arm blocks point up or down. I chose to orientate mine facing upward in the hope that it would collect some oil spray and allow that collected oil to lubricate the rocker shaft further.

Jake

[kevinh]

Hi A51,

I think I'll stay with my Sonex rocker arms for now (already installed - but I will probably remove and inspect per perarmstrongs great find), but for my future use, which CB performance rocker arms are you using?

Kevin

[lutorm]

These are the SCAT ones I got: http://vwparts.aircooled.net/SCAT-1-1-1 ... /20130.htm

I was advised by John at aircooled.net that when used with either the swivel foot or ball adjusters (as opposed to the stock non-swiveling ones), you need to grind off ~0.1" from the bottom of the rockers so the adjusters can sit deeper in the arms. If you don't do this, your valve train geometry will be quite off. After examining the geometry, I agreed and did so. I wrote it up here if anyone's interested.

[gammaxy]

When removing the rocker arms recently to check head torque, one of the steel balls fell out of an adjuster. I've since used a magnet to easily remove two others on that side of the engine. I haven't tried the other side, yet, but suspect similar. The engine is at around 330 hours.

I'm going to replace the adjusters based on the guy at CB Performance saying that's what he'd do. Seems the engine will run happily like this for quite some time and the ball will be retained as long as you don't get a stuck valve. Don't know how common a stuck valve is on our engines.

I'm considering all options for new adjusters.

[Area 51%]

Both ball and elephant foot adjusters are shown in the assembly manual. The Sonex factory Xenos has the elephant foot type adjusters.
Not sure how many hours were on that engine when I had a chance to look at it, but no wear could be seen on the valve stems. Huge contact area. Another really nice thing about the elephant adjusters is not being able to inadvertently get a ball incorrectly oriented.

I'm sure the "ball" type had a better "value" rating than the elephant foot adjusters and were thusly incorporated into the engine kits.

[WesRagle]

HI Guys,

A question for you engine aficionados.

The assembly manual for the AeroVee instructs the builder to offset the swivel from the valve stem.

Questions:

1) Is this done to compensate for the VW's lack of a valve rotater?
EDIT: Never mind, I read more and that is what the offset is for. So, only one question.
2) If so, would the elephant foot adjusters be able to provide the same function?

Thanks,

Wes