Valve Adjusters Revisited - Now also valve lash caps! |
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Valve Adjusters Revisited - Now also valve lash caps! |
bbrock |
Apr 5 2018, 08:58 AM
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#1
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
I know valve adjustment screws have discussed to death, but frankly, the information is all over the mat and the more I read, the more confused I get. I'm hoping to get some clarity for my build. Here's the situation: stock "GA" 2.0L engine. The only mod on this engine is the OE camshaft got a mild regrind for carbs and I installed euro spec (flat top) pistons. This is not a performance build, just looking for reliability.
The heads are in Sonoma being rebuilt right now and, based on advice from this forum, will get a new set of SS valves. I have a box full of rocker assemblies from several engines, including both 8mm and 10mm versions. My original plan was to install the 10mm rockers with a new set of OE adjustment screws, but I have read that SS valves require either swivel foot adjusters or lash caps to protect the stem ends. True or False? Manley valves have hardened tips (IMG:style_emoticons/default/confused24.gif) If it's true that SS valves need extra protection, I like the swivel foot adjuster options, but they are damn expensive and i AM trying to stay in a budget here. Lash caps seems the less expensive option but what is the best way to deal with the extra length they add to the valve stems? Again, I'm just looking for a reliable engine that provides new stock performance. I'm not interested in upgrades that only benefit high performance engines or provide nothing but bragging rights. Thanks in advance for any advice. |
VaccaRabite |
Apr 5 2018, 09:49 AM
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#2
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En Garde! Group: Admin Posts: 13,407 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
You want the elephant foot adjusters if you are making any other valve train modifications to your build.
The elephant feet will also require you to use 1.7 rockers, and clearance them to fit. Zach |
bbrock |
Apr 5 2018, 01:03 PM
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#3
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
Thanks Zach,
My question is, why? I don't doubt the elephant feet are better (quieter, less side loading, better valve rotation, cures erectile dysfunction, etc.), but at a minimum of $250 for a set of authentic Porsche adjusters, those are expensive screws. I want to know that investment will translate into increased longevity of the engine. If the SS valve tips are hardened, why would OE adjuster screws punish them any more than they do stock valves? (IMG:style_emoticons/default/confused24.gif) I have plenty of rockers from 1.7s, my 2.0, and a bus. BTW, is the only difference between 2.0 and 1.7 the size of the adjustment screws? I ask because my 2 liter had 8mm screws (mid-73 MY). My 10mm set came out of a bus. |
mtndawg |
Apr 5 2018, 01:15 PM
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#4
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Member Group: Members Posts: 413 Joined: 26-January 09 From: Granite Bay, Ca Member No.: 9,985 Region Association: None |
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MarkV |
Apr 5 2018, 01:26 PM
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#5
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Fear the Jack Stands Group: Members Posts: 1,493 Joined: 15-January 03 From: Sunny Tucson, AZ Member No.: 154 Region Association: None |
I had Hamm rebuild my heads a few years ago when he was still working on stock 2 liter heads. He used stainless valves and double springs. I am running the oem 8mm rockers and push rods. I am adjusting both intake and exhaust at .006 in. since I don't have sodium exhaust valves any more. No one told me there was any kind of hardness problem with stainless valves.
I can tell you that I wish I would have made the switch to swivels. I know the adjusters are expensive but it's really the only thing I feel like I should have done while it was all apart. Yea I saved a some money but the stock valve train is loud. (IMG:style_emoticons/default/dry.gif) |
bbrock |
Apr 5 2018, 03:10 PM
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#6
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
I looked at those but they came up in one of the many older threads I read and not in a good way. I don't remember the issue, but the consensus was to use genuine Porsche screws. But if something like the CB swivels would make a good sub for Porsche parts, this upgrade would be a no-brainer. (IMG:style_emoticons/default/popcorn[1].gif) I had Hamm rebuild my heads a few years ago when he was still working on stock 2 liter heads. He used stainless valves and double springs. I am running the oem 8mm rockers and push rods. I am adjusting both intake and exhaust at .006 in. since I don't have sodium exhaust valves any more. No one told me there was any kind of hardness problem with stainless valves. I can tell you that I wish I would have made the switch to swivels. I know the adjusters are expensive but it's really the only thing I feel like I should have done while it was all apart. Yea I saved a some money but the stock valve train is loud. (IMG:style_emoticons/default/dry.gif) Thanks Mark, this is very helpful. The sound benefit alone makes the swivel feet attractive. We all know that the stock Type IV sounds like a pound of loose bolts in a washing machine. Part of my resistance here is that this is an upgrade that would be easy to do down the road. Rockers are easy to swap with the engine still in the car. I've done it before. So it isn't like I'm stuck with the choice I make now as long as my choice doesn't wind up mushrooming my valve stems. I'm doing a full rotisserie resto of what a year ago was a pile of rust. If you add every $200-$300 upgrade that would be nice, it doesn't take long before you are 5-10 grand over budget. I'm trying to be careful about sorting out what must be done now, could be done later, and really isn't worth the $$ At this point, I'd put this one in the "could be done later" group but not set in stone. Thanks for everyone's input so far. (IMG:style_emoticons/default/beer.gif) |
MarkV |
Apr 5 2018, 03:54 PM
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#7
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Fear the Jack Stands Group: Members Posts: 1,493 Joined: 15-January 03 From: Sunny Tucson, AZ Member No.: 154 Region Association: None |
Yes.... sounds like someone shaking a coffee can full of rocks.
I don't know if I would go to the trouble of making the change now that it is back together and runs good. Because my heads were cut I had to do the geometry thing with the shims and dial indicator. It can be done with the engine in the car but it wouldn't be pleasant. I had to go back in and change some push rod tube seals that I cant get to seal up. It's a pain to do that with the engine in the car. They still leak but not bad and I would rather drive it than work on it. (IMG:style_emoticons/default/driving-girl.gif) |
HAM Inc |
Apr 5 2018, 06:00 PM
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#8
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
I had a set of these in my shop for a visual evaluation and thought they looked pretty good. I am not endorsing them, just putting it out there as a viable option. Quite a few bus owners have reported good results with them on the samba.
The benefits of a quality swivel screw to guide and valve life are significant. http://www.tp-technologie.de/produkte%20ve...ellsch%20en.htm |
914Sixer |
Apr 5 2018, 06:25 PM
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#9
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914 Guru Group: Members Posts: 8,845 Joined: 17-January 05 From: San Angelo Texas Member No.: 3,457 Region Association: Southwest Region |
I have the 10MM set up that I am going to use on the HAM heads. I had my work done by a guy in LA. Machined the rockers for swivel feet and machined the rocker end shafts to use a solid center spacer with shims so rocker is dead center on top of valve. I was waiting to show set up when the new heads get here.
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bbrock |
Apr 5 2018, 07:04 PM
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#10
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
I have the 10MM set up that I am going to use on the HAM heads. I had my work done by a guy in LA. Machined the rockers for swivel feet and machined the rocker end shafts to use a solid center spacer with shims so rocker is dead center on top of valve. I was waiting to show set up when the new heads get here. (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif) Alright, I'm back in the hunt. Len's confirmation that they do increase guide and valve life is the sort of justification I needed. If the TP screws pan out, it makes it a no brainer since it would be even less expensive than replacing the OE screws with genuine Porsche parts and about the same as after market. You may have answered my question already Mark, but given that I have my choice of rockers, I wonder if there is a benefit going with the 10mm set. I haven't found anything negative about the TP screws on Samba yet, but still digging. Another worm popped out of the can I opened though. Looks like I should use solid spacers on the shafts instead of the OE spring and shim setup? I think I need to read up on setting valve geometry. I was operating under the assumption that only applied when modifications were being made. Last question... for now (IMG:style_emoticons/default/smile.gif) What is the first indication of a crappy adjustment screw? Do the valves just start going out of adjustment fast? I've had the pleasure of driving my bus when a valve broke. Blew a hole right through the case. I need to take care of my matching numbers baby here. (IMG:style_emoticons/default/wub.gif) |
MarkV |
Apr 5 2018, 07:25 PM
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#11
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Fear the Jack Stands Group: Members Posts: 1,493 Joined: 15-January 03 From: Sunny Tucson, AZ Member No.: 154 Region Association: None |
I need to stay off this board... or I will end up doing work on something that I thought was settled. Those adjusters look tempting. I was told fly cutting the heads is what constitutes a change that required shimming the rockers. I also used spacers under my jugs to set the C/R which also is a change that required shimming the rockers. On a rebuild I don't think there is any way to get around doing the geometry thing.
As for going out of adjustment fast I can only say that I probably adjust mine more just because I am trying to keep them quiet. I can tell by sound when it's time. (IMG:style_emoticons/default/confused24.gif) |
VaccaRabite |
Apr 5 2018, 07:34 PM
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#12
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En Garde! Group: Admin Posts: 13,407 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Last question... for now (IMG:style_emoticons/default/smile.gif) What is the first indication of a crappy adjustment screw? Do the valves just start going out of adjustment fast? In short, the swivel head fails. Either jamming in place or breaking off entirely. Usually when the engine is at red line, because Murphy is a bitch. I had a set on my engine for a long time. Upgraded to Jakes full valve train kit with the good screws. Gave my old ones away and one of them failed shortly there after. I felt like crap about that. Zach |
bretth |
Apr 5 2018, 07:47 PM
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#13
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Senior Member Group: Members Posts: 899 Joined: 23-June 15 From: Central TX Member No.: 18,882 Region Association: Southwest Region |
I bought a 68 bus back in 2000 that had 52,000 miles on it. Just to be safe I had the heads rebuilt and bought an inexpensive set of the
Correction: I just realized that I used the swivel ball adjustment screws not the elephant feet. Sorry for the mix up. I wonder if there is a swivel ball option for the type 4? |
bbrock |
Apr 5 2018, 07:56 PM
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#14
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
I need to stay off this board... or I will end up doing work on something that I thought was settled. Those adjusters look tempting. Ha! If you are like me, something like this would wear on me until I break down and do it. I have the benefit of 7-8 months of winter so plenty of garage time to fiddle. Good point about the jug shims. I haven't decked my engine yet so something to keep in mind. I'm learning it isn't as easy as just rebuilding the heads and then bolting all the old parts back on like I did with my bus rebuild. That ran well for about 30K miles until the aforementioned #3 exhaust valve grenaded the engine. I just assumed it was because I had reused valves that already had about 120K on them, but maybe not addressing the geometry contributed. (IMG:style_emoticons/default/confused24.gif) Last question... for now (IMG:style_emoticons/default/smile.gif) What is the first indication of a crappy adjustment screw? Do the valves just start going out of adjustment fast? In short, the swivel head fails. Either jamming in place or breaking off entirely. Usually when the engine is at red line, because Murphy is a bitch. I had a set on my engine for a long time. Upgraded to Jakes full valve train kit with the good screws. Gave my old ones away and one of them failed shortly there after. I felt like crap about that. Zach So what kind of damage did that do Zach? It doesn't sound good but trying to think of worst case. Maybe worst would be bending a valve and crashing a piston into it? Okay, that's pretty bad. |
MarkV |
Apr 5 2018, 08:12 PM
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#15
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Fear the Jack Stands Group: Members Posts: 1,493 Joined: 15-January 03 From: Sunny Tucson, AZ Member No.: 154 Region Association: None |
If you do the adjusters you have to switch to chromoly push rods that you have to cut to length. (IMG:style_emoticons/default/sawzall-smiley.gif)
I noticed these a while back: https://www.ebay.com/itm/VW-Type-4-CNC-Bill...nCa&vxp=mtr The seller looks familiar |
bbrock |
Apr 5 2018, 08:30 PM
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#16
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
If you do the adjusters you have to switch to chromoly push rods that you have to cut to length. (IMG:style_emoticons/default/sawzall-smiley.gif) I noticed these a while back: https://www.ebay.com/itm/VW-Type-4-CNC-Bill...nCa&vxp=mtr The seller looks familiar Those are the spacers I was talking about. Just going by what I read on Samba earlier, but it sounded good... the stock setup uses the spring with shims/washers on the ends between rockers which allows for side to side movement and therefore less precise geometry. But that's all I know. There was a big debate on one of the older threads about adjusters and push rod tubes. It seems you only need custom push rod lengths if you have to shim the rocker assembly to get clearance for the adjusters (or change the deck height). If you don't shim the rockers, you haven't really changed the geometry other than to more precisely align the rockers with the valve stems. This is all new to me but makes sense. |
MarkV |
Apr 5 2018, 08:53 PM
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#17
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Fear the Jack Stands Group: Members Posts: 1,493 Joined: 15-January 03 From: Sunny Tucson, AZ Member No.: 154 Region Association: None |
It's been a while since I did it but I think you shim the rockers so that the rocker tip hits the center of the valve at half lift. If I remember correctly this issue is that you don't want the rocker to put all of its movement on one side valve or the other which would cause premature wear on the valve, the tip & the guide. There are some great write ups around here about how to set it up.
Kind of like this but different: http://www.lunatipower.com/Tech/Valvetrain...inGeometry.aspx |
jjs3rd914 |
Apr 6 2018, 10:44 AM
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#18
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Member Group: Members Posts: 124 Joined: 8-August 04 From: Sarasota, FL Member No.: 2,476 |
Subject valve lash caps??
Okay who has experience with the old school valve lash caps? I was going to start a new thread but am jumping in here. Am doing a 2056 build and have on order a new set of AA heads (44 by 36 SS valves) with weber 40IDFs, WebCam 086 grind, 96mm AA flat top pistons/jugs, etc So I have a set of 1.7 8mm and 2L 10mm rocker arms. Just found a set of valve lash caps from my FV racing days and was wondering about using them with the 10mm 2L rockers instead of going the the pricey road of genuine Porsche swivel feet. Car is to be a low mileage daily driver. I understand they might change the geometry which will be checked and set either way. Any comment on going this route and longevity. I also have read where the SS valve are a little softer or just Urban legend??? YES I am very interested in the TP swivels. If they turn out to be on par with the Porsche ones, which rockers should I use them on, the 8mm or 10mm set, since they can supply either? http://www.tp-technologie.de/produkte%20ve...ellsch%20en.htm Thanks jjs3rd914 |
bbrock |
Apr 6 2018, 12:48 PM
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#19
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
Subject valve lash caps?? Okay who has experience with the old school valve lash caps? I was going to start a new thread but am jumping in here. Edited the thread subject to include lash caps... (IMG:style_emoticons/default/popcorn[1].gif) |
brant |
Apr 6 2018, 01:35 PM
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#20
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914 Wizard Group: Members Posts: 11,584 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I'm not a builder...
but I "believe" setting the valve train geometry should be done on any rebuild at this point.... if your pushrods are the wrong length... you will not get the benefit of an aftermarket lift/cam I suppose it might be safe to say that valve train geometry be set any rebuild that changes from the stock cam?.... or just any rebuild |
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