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valve springs and valve train wear
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SGKent Premium Member
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PostPosted: Fri May 01, 2009 12:31 pm    Post subject: valve springs and valve train wear Reply with quote

I don't visit here much anymore because to be frank, it was too tiring to read the arguments from know-it-alls. So, if I disappear again you will know why. That said-

The reason this thread is being started is that I tried to buy some NOS valve springs to safeguard my new reground Webcam. The only ones I found so far were from a Samba member selling what they believe are 021109623E springs. Another source has some but this issue really deserved exploration because there are many posts here of sunken valve seats and worn cam lobes. There are also posts of people who couldn't get their hydraulic lifters to adjust because they had the wrong springs - and evidence that some pushrods are bowing from having too strong of springs. Here is part of the problem, springs are a black box item - you trust what is in the box being sold to you is the correct part. There is no definitive source for spring specs and the parts aren't stamped with numbers. Bentley and Wilson agree on some specs but my machine shop who has 30 years experience with specifcally VW type 1 and type 4 has other numbers. So I am starting this thread and if you have EXPERIENCE with the data feel free to chirp in.

Here is what I have so far which is not much.

I bought a set of 8 SUPPOSEDLY NOS Brazilian 021-109-623E valve springs from a Samba member. According to the Orange book VW supplement,

021109623K are 1.331 OD
springs prior to /K are 1.291 OD (doesn't say if just /J or /C thru /J
these are about 1.32 OD so they match neither but maybe the Brazilian are different.

These are open length of 1.93" , a wire size of .1775" and an ID of .962"

They test at:
29mm 102 lbs which is type IV test but would be 168-186 per Wilson & Bentley
31mm 86 lbs which is type 1-3 test but would be 117 – 135 per Wilson & Bentley
33.4 mm 72 lbs which is 40 hp test but would be 80+ per Wilson

Who knows what these NOS springs are as they align with nothing that is published – although they would be PERFECT based on what my machinist told me verbally off the top of his head last month for the early Type 4 solid springs (80 to 90lbs is what he said at 31mm). That also agrees with a post I found online as to what another person was told by a different well known VW machine shop. Bob Hoover however posts 117 to 135 lb for all post 1967 VW springs so there is another opinion. These springs are also evenly spaced coils and not wound closer at the bottom.

Using Bentley, Wilson and Bob Hoover data:
Type 4 are 168 – 186 lbs at 29mm
type 1-3 are 117-135 lbs at 31mm.
40 hp are 89 – 102 lbs at 33.4 mm

From my perspective, this could be a disaster for someone who wonders why their engine runs rough at higher RPMS if valve float starts, or why someone else who gets HD springs wonders why their cam failed in 5000 miles. However if these springs are true E’s (including Porsche 914 & 912E) and VW didn’t tell anyone that they doubled the spring tension for increased longevity of springs in 1975 or so, it might explain why high spring tensions resulted in cam and cam bearing wear and partially why seats pound into heads. Now I am not trying to second guess VW here, but this area needs exploration because you cannot walk into VW and order the correct springs for your bus any longer. You must trust that what you are handed in the black box is correct and there is no standard to test off of. And - if E springs are that much softer than J, then it might explain this statement from a well respected Samba member as to valve train wear, "i'd say the 1.7 and 1.8 engines have the least wear." The E spring was used on the 1.7 and 1.8 engines. Was VW worried about stack fires or smog issues if a spring got weak and failed to close a valve on an FI engine? Were they anticipating higher RPMs than the 914 engine? (I don't see how but I am told by parties who were there at the time the 914 was sold in Germany as a sporty VW whereas here it was a Porsche.) As these engines get older and we must rely on more used parts, I think this area needs addressing and I plan to address it. If you have already done valve spring testing and have input then your feedback is appreciated. If you just want to make comments on the subject that contribute great but stay to the point and don't hijack the thread to talk about the time your engine died in the desert and you and your dog walked 15 miles for help with only a beer in your hand and a piece of rattlesnake meat to chew on...
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PostPosted: Fri May 01, 2009 2:56 pm    Post subject: Reply with quote

You might get some input if this was in the Engine/Performance forum.
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PostPosted: Fri May 01, 2009 3:40 pm    Post subject: Reply with quote

SGkent...They sound just a little bit light at load. As you note, stock type 4 are loaded at 176 lbs at 29mm at rest.
Now...that being said, there is no reason that you couldn't say...use a different retainer and possibly shim the spring pockets a little to get some better at rest/loaded height tension...as long as there is enough travel that you do not get coil bind at maximum lift...at temperature.

Also....interesting. Just for clarification.....were any of these PR bowing problems on hydraulic? Is so they had the wrong pushrods as they should besteel not the aluminum.
Also...In general they had to be at ugly tension for the stock pushrods to bow.
Also ...for clarification, what do they see that causes them to think the PR's are bowing. I ask because I have never seen it and would not be surewhat to look for unless I could see it while setting up valve geometry.

Just a thought....but I know Jake Raby sells very carefully thought out valve spring sets. It may be worth contacting him as well.

My last set were actually some modified chevy springs my brother the engineer installed. They ran excellently with a web 73. He used them precisely because the set of type 4 spec'd springs I had (i'll dig out the part # I hope)...were a alittle light he felt...but would have required an excessive shim in the valve pocket.

I was very leery of installingsomething totally different. But...they tested out to right at 125 psi at stock 29mm give or take .5mm for the shim.

The really important thing is that the springs have enough seating pressure to (a) keep the valve closed and (b) no be excessive at full lift.

I'll see what I can find for half and full ift specs. If you could the spring tensions at half and full lift on that set...it may help you.

As you note....you drop from 102 to 86 psi over 2mm of compressed length ...right? Just thinking linearly.....

If you end up replacing valve seats and have a bit more valve margin...allowing the stems to not protrude to high....if the coil diameter allows, you might be able to start slightly more compressed and pick up another say 20 psi and still have no coil bind at full lift. Just some thoughts. Ray
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PostPosted: Fri May 01, 2009 5:32 pm    Post subject: Reply with quote

this thread was about stock valve springs - parts which are NLA. It is not about performance or racing, quite the contrary.

Ray - thank you for your help. The issues are there mostly because people have been rebuilding and switching parts for some time now. Read this post and you will see the significance of the issue.

Quote:

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Posted: Thu Jan 19, 2006 8:27 am Post subject:

--------------------------------------------------------------------------------

Success! It was the valve springs after all. I found a set of correct 623K's at a local shop, put them in, set the tappets 2 full turns from contact, and now I have type 4 Hydraulic lifter bliss-smooth and quiet! So I've learned a few things. Never assume your shiny newly rebuilt heads were done right (or anything that has been messed with by somebody else somewhere along the line....). The springs I removed were a full 3/32" shorter than the new ones, and varied as much as 1/32" in free height. They looked the same otherwise, so they may have been the right ones, but they were clearly worn out.

By the way, it's a lot easier to replace the springs than it is the lifters! I made a tool from a tie-rod removal tool, pumped the cylinders to 100 psi with my air compressor, and that was it. 5 minutes per spring once I was set up.

Thanks for all the replies.


Ray said:
Quote:
They sound just a little bit light at load. As you note, stock type 4 are loaded at 176 lbs at 29mm at rest. Now...that being said, there is no reason that you couldn't say...use a different retainer and possibly shim the spring pockets a little to get some better at rest/loaded height tension...as long as there is enough travel that you do not get coil bind at maximum lift...at temperature.


need specs - don't want people switching retainers and shimming springs. Want people to be able to find the right springs for their buses in one 5 minute phone call and not suffer through 100 hours of research on what cam and springs were stock. Don't want to see posts of 5000 mile cam failures like we see now. Coil bind only affects you when you either have a high lift aetup or the wrong spring.

Quote:
Also....interesting. Just for clarification.....were any of these PR bowing problems on hydraulic? Is so they had the wrong pushrods as they should besteel not the aluminum.
Also...In general they had to be at ugly tension for the stock pushrods to bow.
Also ...for clarification, what do they see that causes them to think the PR's are bowing. I ask because I have never seen it and would not be surewhat to look for unless I could see it while setting up valve geometry.


Because the /K spring is so much stronger than the /C, /E or /J so when it is used or people buy HD springs in a nice package they overpower the aluminum rods. The rods sometimes show signs of rubbing on the pushrod tubes and roll funny on glass from being bent. It isn't the cam or lifters that over powers the rod. It is the spring.

Quote:
Just a thought....but I know Jake Raby sells very carefully thought out valve spring sets. It may be worth contacting him as well.


His site shows high rev only. I want a list of factory specs on the springs before deciding to change things. The stock springs are fine for standard driving. I also believe part of the reason the seats sink into the heads besides heat is too high a spring pressure. Remember - at one point in my life I built and flowed heads for a living. For street driving I think the lightest factory springs for the engine type or equivilent will be best. This will not be a high rpm engine. Likewise if you decide two years from now to build another engine and need springs, you will want a valid chart to decide from what you want. One does not exist.

Quote:
My last set were actually some modified chevy springs my brother the engineer installed. They ran excellently with a web 73. He used them precisely because the set of type 4 spec'd springs I had (i'll dig out the part # I hope)...were a alittle light he felt...but would have required an excessive shim in the valve pocket.

I was very leery of installingsomething totally different. But...they tested out to right at 125 psi at stock 29mm give or take .5mm for the shim.


Using crossover parts is not always a bad thing when you know specs going in. 125 pounds on a type 1 engine would be perfect. Since type 4 list at 168 - 186 it would seem light but RIMCO said 80 - 90 so until I get some testing done I don't know what was really on type 4 engines new. There are 3 different springs listed for it. /E, /J, /K

Quote:
The really important thing is that the springs have enough seating pressure to (a) keep the valve closed and (b) no be excessive at full lift.


yes - well said

Quote:
If you end up replacing valve seats and have a bit more valve margin...allowing the stems to not protrude to high....if the coil diameter allows, you might be able to start slightly more compressed and pick up another say 20 psi and still have no coil bind at full lift. Just some thoughts. Ray


heads were done by RIMCO. I asked them to replace the seats, weld and re - anneal the heads. Just want stock. Never would have bought this bus last year had I known how hard it would be to get simple things like valve springs. Took me 4 tries to get a solid lifter reground cam. Had someone tell me today they had a new NOS hydraulic they just bought when in fact it was a solid. They had been looking for one and had it in their hands and didn't know it.

This thread is about nothing more than finding the specs of the four bus valve spring types C/ E/ J/ K/ and publishing them. When I am done I will print and lamintate it and send a free copy to every place that sells camshafts and springs. Then when someone like me calls and asks for a cam, lifters and springs they can answer the questions on what they have in 5 minutes or less.

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Jake Raby
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PostPosted: Sun May 03, 2009 6:13 pm    Post subject: Reply with quote

Spring ratings are only one method of measuring a spring's effectiveness. On more than a few occasions I have seen springs with better dampening characteristics rate very similar to another, but control the valves to a much higher RPM.

Most people don't have the ability or opportunity to rate springs after they have been ran with various cams for different amounts of time in different applications.

I have done this with the spring packages that we use, both with and without cryogenic enhancement and isotropic super finishing.

In short, a spring's rate when new is not the only aspect that one should use when choosing a performance spring.
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Bob Hoover
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PostPosted: Mon May 04, 2009 9:08 am    Post subject: Reply with quote

Jake Raby wrote:
Spring ratings are only one method of measuring a spring's effectiveness.

------------------------------------------------------------------------------

Probably just me but... fifty(!!?) springs in the carton on the shelf. Kid doesn't know S... from shoe polish. some are progressive, most aren't. Dicker for a while, take the whole box home with me.

Measure them for pressure @ a given length. Sort them into sets.

Some are pretty wild. Like, 208 lbs. On some, the wire diameter is different. (Mark them with fingernail polish.)

Record them by POSITION, standing there like soldiers on parade atop a piece of 3/4" thick aluminum tooling plate. Four rows of four, one row of five.

Bake them @450 F. for about 3 hours. Allow them to cool in place. (Actually, FORGET about the damn things until I stumble across the notes, go look in the oven.) Hurts to test them. (Hurts to do anything, nowadays.) Indexed by the row of five, remeasure them for compressive strength. Surprise!

Some -- the ones WITH progressive winding -- don't change all that much. But a couple of the non-progressively wound HIGH TENSION springs aren't even springs any more. Tester mashes them down... and they stay there, leaving me saying 'Ah ha! Grasshopper.'

Ah ha indeed.

I needed two sets of a fairly low value. Intakes higher than exhausts. Got that.

Why the 'test'? Because what works in a liquid-cooled engine may be unsuitable for use in an air-cooled engine. And it was obvious the shop had no idea what lurked in the box marked 'VALVES.'

-Bob Hoover

PS -- For Jake.
I tried to call you, as per your request. You apparently have too many phone numbers. Ditto for internet addresses. If you want to get in touch I suggest we try it the other way 'round. [email protected] Same phone & address since 1965. (Or we could play a little Morse Code on the 20 meter band... :-)
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PostPosted: Mon May 04, 2009 10:03 am    Post subject: Reply with quote

Welcome back SGKent. Everyone needs a good laugh. So hang-out.

When i was a kid i would shoot seats & grind valves after school. V8 where $12 and 6 cyl were $6. Yes the Know-it-alls.

The biggest or 90% of the problem with valves and cam is break-in. How long can you crank a 125lb spring load on a lifter or cam without oil. Yes the distributor out by 40 degrees and yes i know zero about the carb.

Stick around it so amusing Laughing
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PostPosted: Mon May 04, 2009 11:27 am    Post subject: Reply with quote

Thanks Terry.
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PostPosted: Mon Aug 17, 2009 10:26 pm    Post subject: Reply with quote

EDITED - I am unable to edit the results above this line so please be aware: the pressures reported above this line have to be multiplied by 2 to be correct. The numbers below take the 2x into consideration.


resurecting the thread as getting ready to put the engine together. Wanted to report back what I found. I think the results say to effect - you are on your own when it comes to completely trustworthy valve springs that meet published specs. You'll notice that of all the sets, only the used springs for a type 1 fell within all specs, although all of the sets would have been close enough to run. I did not bake any so that might lower the results to within spec (although none were progressive except for the used ones.) Once I pull the springs off my rebuilt type IV heads I will add those results to this thread.

The closest Type IV springs were the /E Brazilian ones; the ones that would give the best results at a higher RPM would be the NOS /J ones from Mick Motors.

Factory specs valve springs per Bentley and Orange book

Type 4

Published specs:
Valve spring OD 1.291" thru /J, 1.332" for /K
Loaded length 29 mm (1.14")
Pressure should test at 168 - 186 pounds
progressive - yes

spring set A
purchased from Samba classifieds. NOS brazilian type IV - 021-102-623/E
Valve spring OD 1.330"
tested at 186 - 190 pounds
Progressive - no

spring set B
purchased from CIP1. Sold as new type IV - 021-102-623/E
Valve spring OD 1.345"
tested at 216 - 236 pounds
progressive - no

spring set C
purchased from Mick Motors new from VW type IV -021-102-623/J
Valve spring OD 1.325"
tested at 226 - 228 pounds
progressive - no


Type 1

Published specs:
Valve spring OD not given
Loaded length 31 mm (1.220")
Pressure should test at 117 - 135 pounds
progressive - yes

spring set D
purchased CIP1 new 113-109-623/C type 1 - 1600
OD 1.225
tested at 140 - 142 pounds
progressive - no

spring set E
purchased used 1600 DP springs Samba classifieds
OD 1.220
tested at 120 - 132 pounds
progressive - yes
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PostPosted: Tue Aug 18, 2009 9:45 pm    Post subject: Reply with quote

See this post and the one above it for spring results.

I have no way of knowing if these are the original springs that came with the heads and if they were solids of hydraulics at birth. These are the results on the springs that came back with the valve job.

Factory specs valve springs per Bentley and Orange book

Type 4

Published specs:
Valve spring OD 1.291" thru /J, 1.332" for /K
Loaded length 29 mm (1.14")
Pressure should test at 168 - 186 pounds
progressive - yes

spring set F
Used w/ heads. Assumed to be 021-102-623/J but could be /K or ?
Valve spring OD 1.335 average result (1.335 - 1.370)
tested at 210 - 228 pounds. All but one low one grouped at 222-228
Progressive - no
Note: uncompressed lengths were similar except low one was .030 shorter

Final observations. None of the "VW" springs tested at Bentley. The Brazilian were closest. I think there is a good chance that VW did not consider variances in spring pressures to be critical and may have varied from run to run. Although I looked everywhere I could, I have yet to find NOS springs of /E , /J or /K that are in OG packaging. Also, the Orange book shows 1.291 as the OD of springs prior to /K. You will note that none of these springs came back at the 1.291 inch diameter. All were closer to the /K diameter. I assume the ones that came off the heads I have are the same ones that were on it when it died. That cam had the typical wear on it, and the wear pattern suggests that the lifters were in contact with the cam constantly, without lofting. This makes me suspect that for a street engine the OG /J and /K springs were over-kill based on reports that the earlier engines and 914 engines had less cam wear.
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PostPosted: Wed Aug 19, 2009 2:19 pm    Post subject: Reply with quote

EDITED:

Looked up some numbers at Isky. For stock applications they used 170 pounds per inch of lift which at 1.14 (29 mm) works out to 193 pounds. For HD applications they used Chevy springs that were 240 pounds per inch which works out to 273 pounds at 1.14 (29 mm).

I'd be interested in hearing what numbers come up for springs that are guaranteed to be from about a 1974 T4 engine, VW or Porsche.

ADDED:
Tonight I took some time to measure the wire gauges on all these springs. I have now come to the conclusion that the /E Brazilian ones at 190 pounds are indeed meant to be /E. The /J for the 2.0 engines is supposed to be heavier and indeed, the /J I got from Mick Motors are about 40 pounds heavier than the Brazilian ones. The ones that came on the engine came from a rebuilt engine so I don't know their history but the wire gauge matches that of the /K springs and is thicker than the ones from Mick Motors. Considering they are about the same force as the /J but they are used, I believe that they are indeed /K (hydraulic) springs.

I will probably follow Bob Hoover's blog and cook each set then measure them again. The Brazlian would probably be easier on the cam if the RPM is kept down. If I plan to push it then the /J from Mick Motors is what I will use unless a bonafide set of German /E's (914 1.7/1.Cool or /J's (2.0) falls in my lap.
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PostPosted: Fri Aug 21, 2009 11:17 pm    Post subject: Reply with quote

Final valve spring post. We are going to use the lighter springs (/E) we bought on Samba as the are the closest to Bentley as long as they pass the heat test of Bob Hoover.

FYI - We found some Isky springs for a 914 that have the perfect tension - 120 pounds at rest 1.5" and 190 pounds at 1.14" loaded, really smooth travel, chrome silicone steel but the spring size ID is just barely too small for stock T4 retainers. If you don't mind getting new retainers and possibly cutting the area around the guides a few thousandths, the 205-G Isky springs would work well IMHO. $40 a set of 8 directly from Isky (but you will need different retainers or turn yours).
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PostPosted: Wed Aug 26, 2009 6:45 pm    Post subject: Reply with quote

I lied about the final post. This came in today re Scat 20138. Based on the pressure at 1.5" they are really too strong for my needs and close to a /J or /K. The ISKY was 117 pounds at 1.5" and the Brazilian /E (914)was 100 pounds. These are probably around 215 - 220 pounds at 1.14. About 190 would be optimal I think for a stock engine that will live below 5,000 RPM. If you are going to push it above that you may need stronger springs.

HI Steve
# 20138 valve spring kit @ $ 41.95
@ 1.500” installed height have 135 lbs seat pressure
I do not have pressure at lift
Valve spring OD is 1.250”
ID is .928”
coil bind in catalog says .900” = 230 lbs
Scat Enterprises
310-370-5501 ext 133
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PostPosted: Thu Aug 27, 2009 6:07 am    Post subject: Reply with quote

Quote:
I also believe part of the reason the seats sink into the heads besides heat is too high a spring pressure.



This assumption is probably the most common mistake made in spring choice, actually sinking valve seats, heavily worn seat & valve contact surfaces are signs of loss of valve control most often caused by insufficiant spring pressure for rpm range.
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PostPosted: Thu Aug 27, 2009 9:25 am    Post subject: Reply with quote

Quote:
This assumption is probably the most common mistake made in spring choice, actually sinking valve seats, heavily worn seat & valve contact surfaces are signs of loss of valve control most often caused by insufficiant spring pressure for rpm range.


you are stating a common myth. It would be appropriate to say that the most common mistake is not defining the use parameters of the engine first.

All that is required on any valved engine is that the springs be adequate to keep the lifters from lofting and be durable. The inertia from the combined mass of the valve, spring, retainer, rocker, pushrod etc and cylinder draw must be controlled by the spring so that the valve follows the cam profile and seats itself for a specified period during each cycle of the engine. On an engine that is designed for long lower rpm service you want the springs to be as light as possible without being so weak they loft. On a race car (drag or track) where the cam profile is more radical and the lobe ramp speeds are greater, combined with higher RPM's, the springs must be substancially heavier. Whereas a 450 - 650 pound spring might be used on a 1/4 mile drag engine, along with titanium parts to lighten the mass, 200 pounds might be more desireable on a long life service vehicle. Likewise if the engine is a Honda OHV with a lighter valve mass, springs will be quite light compared to a pushrod engine. The notion that heavier springs are always better is an absolute myth.
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PostPosted: Mon Mar 28, 2011 10:22 pm    Post subject: Reply with quote

Got some new old stock /E springs from VW Germany tonight. VWOG verified they are West German made old stock prior to shipping. Still have a little cosmoeline on them. I did a quick test and tried one on the tester - tested at 194 pounds at 1.14" (29mm). These were used on the 914-4 engines too.

An update on the /E's I am running on my 1977 FI Bus with a stock FI WebCam. Re-tested all the springs last year when I changed the cam to see if any showed changes after heating. At 1000 miles all were exactly as installed. Have run the engine past 5000 RPM several times to see if it would hold together and whether I could feel any bounce - it was still pulling strong at 5,200 RPM so I would say the /E are excellent springs for street motors. If you need some, VWOG still has them and they run about $10 each to get them here.
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