• Welcome to the new SAOCA website. Already a member? Simply click Log In/Sign Up up and to the right and use your same username and password from the old site. If you've forgotten your password, please send an email to membership@sunbeamalpine.org for assistance.

    If you're new here, click Log In/Sign Up and enter your information. We'll approve your account as quickly as possible, typically in about 24 hours. If it takes longer, you were probably caught in our spam/scam filter.

    Enjoy.

valve spring question

mbruskin

Donation Time
I have an extra head that came with my car when I bought it 5 months ago. I decided to have it pressure checked, ported and polished, which has been done. The valve springs I bought as part of a valve package are too high. The Isky valve springs for the Alpine are the same height. My machinist says they are too high by about a quarter inch. The new valves fit fine and are the same size as the old ones that were removed.

The spark plug holes are different than on my series 5. They are not tube shaped but are more oblong. I can get the proper valve springs but my concern is if the stock springs don't fit, will the head bolt to the block okay. Are there any Rootes aluminum heads that will not fit on the block?

I have the casting number, 1980981, but don't know where to cross reference it.

Any ideas?

Thanks,

Murray
 

RootesRacer

Donation Time
You set spring height by spring pressure.

The workshop manuals give the spring height data and pressures for each.

Its up to the mead builder to determine if the springs can be accommodated in your head and if additional machining or shims are needed in order to function for you.

Keep in mind though that the spring pressures and spring rate are going to be higher for the isky springs as compared to stock regardless of where you set spring height.
 

mbruskin

Donation Time
It seems that what companies are calling "stock" springs are too tall for this head. The old springs were 1 3/8" high. This is why he is saying the 1.7 inch "stock" springs won't work, the pressures will be too high. I don't know where to get different springs. What do other people do?

Murray
 

jumpinjan

Bronze Level Sponsor
Please describe what the head looks like. You might have a very late series V head (with the large spark plug openings), and yes, they take a different and shorter valve spring. I have installed the longer springs (stock springs) as a temporary measure until I could find the right springs and it ran just fine. They were in there for about two years.
Don't use those Isky springs, use just the stock ones.
Jan
 

mbruskin

Donation Time
The head has the 2 half moon markings and the 3rd box or rectangle used for head depth. The only other thing different is the larger oblong spark plug openings. The new valves are the same size as the old ones that came out. I had a feeling that it was a late series 5 head.

Where do you buy stock springs that are shorter?
 

Tom H

Platinum Level Sponsor
Jan, Are you saying that the newer heads (without the spark plug tubes) use shorter springs than the earlier heads? Or is this about some other head introduced even later than the non-spark-tube ones? I had never heard this before. I thought all the geometry of the 1725 heads was the same.

Tom
 

jumpinjan

Bronze Level Sponsor
Tom,
Yes, the later heads had a different shorter spring, and also a very thick spring shim.
jan
 

JConstable

Donation Time
Uh Oh, my blood pressure is rising.....

I just (and I mean within two weeks) finished my engine with among other things a new head (of the later SV style with oblong spark plug openings) and had it surfaced, valves ground....and now the part that really hurts.... had new Isky springs installed. The idea that valve springs differed between the two head styles had not been mentioned - or at least I had not seen it - on the forum.

I have not run the engine thankfully, but what is the damage that would occur?

And finally to echo mbruskin's question, what would be the appropriate spring replacements and where would I get them? Arrgghh!!, I though I had the engine complete!

John
 

RootesRacer

Donation Time
So did you just tell the head shop to install the springs and he didnt ask for any specs?

I have several of the heads without the sparking plug tubes and they are running (IE came with) dual springs.

I know the later hunter type engines ran single springs, but I have to believe that all alpines came with dual springs from the factory.

In any case, I wouldnt run the motor till I did a seat pressure measurement and get a "rate" measurement to make sure that the cam wont go flat (or float the springs). Wouldn't hurt to make sure the coils wont bind too.
 

JConstable

Donation Time
RootesRacer,
In response to your first question: Ummm, Errr, Well......Yup, I was under the impression that the Isky 625/626 dual springs were a direct fit. Obviously in hindsight the head difference (early to late heads) and to a lesser extent the valve grind itself that will change spring geometry. I guess my best recourse is to pull the head and have my head guy (no, not my shrink) check the seat pressure and the spring rate. I presume that the target values for these measurements are in the WSM-145.

Your comment also suggests that the Isky springs your thinking of are single springs not dual. I mentioned the model number above to make sure we are speaking of the same springs.

Finally, if the springs are exerting to little pressure presumably they are shimmed, whereas if the reverse is occurring then you are out of luck (unless you want to be destructive and do something radical like grind into the head to allow the spring to stretch out a bit).

Please keep educating me on the subtleties of Alpine operation - Thanks
John
 

65beam

Donation Time
valve springs

i have a complete 1725 that came out of a series 5 that is 40 something cars from the end of production. it has the new style head with single valve springs. the block also has the side engine mounts cast in the block.
 

JConstable

Donation Time
Speedy Spares lists the following:

P48449 Valve Spring Set (8 Pairs) series I-IV £12.50

1241631 Valve Springs (Single) (8) Alloy Head £10.00

No other information is provided and I think does not necessarily clarify the situation as it implies that series I-IV had dual springs, while series V had single springs. My thoughts based on this thread was that early/mid series V had duals and only much later series V with the new head design had singles. John
 

jumpinjan

Bronze Level Sponsor
had new Isky springs installed. The idea that valve springs differed between the two head styles had not been mentioned - or at least I had not seen it - on the forum.

I have not run the engine thankfully, but what is the damage that would occur?

Don't run the engine. Get those Isky springs out of there. Depending on what cam you installed, the spring coils could bind, and you will get a "lock" which would be bad for the whole valve train. The factory spring is okay, I have checked the coil bind with a Delta KB cam, it doesn't bind, but if you go that route, you should verify your's that it doesn't bind too. Don't use any shims, just the steel cup washer.
Jan
 

mbruskin

Donation Time
Jan:

If I understand you correctly, the standard springs may work okay without the shim on the head that takes the shorter valve spring. I realize that my head would have to be checked to be sure. Where do I get standard springs? SS and Classic don't carry them. VB has them but they scare me. Where would you buy them if you needed them?

Thanks,

Murray
 

JConstable

Donation Time
Jan,
Ok, expanding your post. As I understand the situation it is suggested that I pull out the Isky springs and replace with old factory springs; then check to (i) ensure that the compressed springs do not bind;
(ii) be sure that springs exhibit suitable seat pressure (wsm-145: inner 35.9 lbs; outer: 70.8 lbs); and
(iii) ensure the springs have a suitable spring rate (What are the spec values here? they are not clearly indicated in wsm-145).

Presumably, if my old springs meet the criteria above I can use them, however, my machinist indicated that the springs were not consistent (greater than 10% variation among springs) and hence I purchased the Isky springs. Rather than use old variable springs in the re-built engine, I would prefer new. Therefore, can I use any available new springs (single or dual) that meet the criteria above AND fit in the available space on the valve (wsm-145: inner fitted length: 1.43 inch; outer fitted length: 1.55 inch)? Thanks for any guidance. John
 

RootesRooter

Donation Time
Couldn't the springs be visually checked for binding just by rotating it with the handcrank?

I agree that if you install a hot cam, you should check for binding with any spring used. I tried out an H120 grind several years ago but didn't check for binding with the stock springs. Several bent push rods and broken rocker arms later on a break-in 350-mile trip ("The Weekend from Hell"), out came the cam. I think the binding problem is why Chrysler/Rootes reached way back into their parts bin to re-use a relatively soft, Mark Husky valve spring on the H120.


Don't run the engine. Get those Isky springs out of there. Depending on what cam you installed, the spring coils could bind, and you will get a "lock" which would be bad for the whole valve train. The factory spring is okay, I have checked the coil bind with a Delta KB cam, it doesn't bind, but if you go that route, you should verify your's that it doesn't bind too. Don't use any shims, just the steel cup washer.
Jan
 

RootesRacer

Donation Time
Couldn't the springs be visually checked for binding just by rotating it with the handcrank?

I agree that if you install a hot cam, you should check for binding with any spring used. I tried out an H120 grind several years ago but didn't check for binding with the stock springs. Several bent push rods and broken rocker arms later on a break-in 350-mile trip ("The Weekend from Hell"), out came the cam. I think the binding problem is why Chrysler/Rootes reached way back into their parts bin to re-use a relatively soft, Mark Husky valve spring on the H120.

Well the real H120 wasnt intended to revved beyond 5000 RPM, so they didnt need a lot of spring.

Can you confirm that only the hunters had that soft single spring even though the late SV alpines used the same head casting?
 

jumpinjan

Bronze Level Sponsor
Jan:

If I understand you correctly, the standard springs may work okay without the shim on the head that takes the shorter valve spring.
Well, all I said is that they will fit, but I don't leave them in. Get the correct springs. I have seen some on Ebay, maybe try Ebay for some NOS springs?
Jan
 
Top