Renamed: Camshaft identification help???

gcracker · Post by **gcracker** » Jun 22, 2009 5:06 PM

Looks like my machinist made a little boo-boo when adjusting my valve clearances. One of the tappets (#12 exhaust) was dropped or otherwise dinged and has taken a bite out of the nose of the cam on every pass. The hardened surface is slowly being shaved away...

Unfortunately, I am 90% sure the responsible parties will cry innocent, or say that I must have done something wrong. Unfortunately, I have been finding little errors here and there that make me wonder: No matter how good your machinist is, the work coming out of the shop is only as reliable as the dumbest guy working for him.

Tucker · Post by **Tucker** » Jun 22, 2009 9:07 PM

Why is a machinist doing your valve adjustment?

DRP535 · Post by **DRP535** » Jun 22, 2009 10:34 PM

The S38B35 cams are only 248° duration??? Wow.

gcracker · Post by **gcracker** » Jun 23, 2009 10:19 AM

Tucker wrote:Why is a machinist doing your valve adjustment?

Cuz they also bored the block, ordered custom pistons, replaced valves and tappets, cut new seats... They're more of a full-service engine shop. ( www.rlengines.com )

The previous screw up shop cut the valve stems to adjust. This shop has the pucks on hand.

P.S. They are taking responsibility so far, and are having me send the cam and tappet to look at.

Post by **mooseheadm5** » Jun 23, 2009 10:45 AM

That is a standup shop taking responsibility. PM photopark or paul burke. I am sure they can hook you up. If I had the money, I'd upgrade to an E34 cam. I know where I can get one, but I'd have to get $250 for the M5 cam just to make a dent in the price. PM me if you want to either buy mine or want info on where to get the E34 cam.

Philo · Post by **Philo** » Jun 23, 2009 9:22 PM

2nd the e34 cam upgrade..., that's what I'm running.

gcracker · Post by **gcracker** » Jun 24, 2009 8:31 AM

Philo wrote:2nd the e34 cam upgrade..., that's what I'm running.

Ok... want to underline the benefits for me?
Top or bottom end?
I know I've read it before, but my long absense washed it from my memory, and I'm always researching so much for school, I avoid google, lately.
Will I need to worry about interferance?

(Yes... I'll search, also. I wouldn't want to start a flame war like I remember from more commercial forums)

wkohler · Post by **wkohler** » Jun 24, 2009 5:54 PM

S38B36 cams are 264°. More duration. Better happiness.

Post by **mooseheadm5** » Jun 24, 2009 5:58 PM

Interference with pistons will only happen if timed wrong. Interference with other stuff will not be a problem either. The cam bolts right in. Go for it, since I can't throw down the bills right now. Either that or buy my B35 cam so I can

gcracker · Post by **gcracker** » Jun 24, 2009 8:33 PM

mooseheadm5 wrote:Interference with pistons will only happen if timed wrong. Interference with other stuff will not be a problem either. The cam bolts right in. Go for it, since I can't throw down the bills right now. Either that or buy my B35 cam so I can

I only worry that since I have what appears to be a cam from the M635, my valves are all set with that smaller base circle in mind, so I would then put what is on the intake now over on the exhaust, and put the b36 cam on my intake. In that case, I will need to have adjustments to both sides made, yes?

Maybe I'm missing something about hydraulic lifters, because they should be able to take up slack, but....

rcbmw · Post by **rcbmw** » Jun 24, 2009 9:23 PM

gcracker wrote:I only worry that since I have what appears to be a cam from the M635, my valves are all set with that smaller base circle in mind, so I would then put what is on the intake now over on the exhaust, and put the b36 cam on my intake. In that case, I will need to have adjustments to both sides made, yes?

The M635CSi M88/3 engine uses a 264° cam that has a smaller base circle (-1mm) than the camshafts found in the S38-B35 or B36. Given this, I would confirm which cam your engine has.

Best,
RCBMW

Rich Euro M5 · Post by **Rich Euro M5** » Jun 24, 2009 9:32 PM

gcracker wrote:Maybe I'm missing something about hydraulic lifters, because they should be able to take up slack, but....

None of the S38/M88 series engines had hydraulic lifters. Personally, I think you should search places like eBay, the Yahoo [s38-m88] list, etc for a set of S38B36 camshafts. Then pay to have the valves readjusted. Now if your valve stems were cut in length to compensate for the smaller base circle of the M88/3 cams, you'll might need to find one as a replacement, I don't know if there's enough adjustability in the shim sets to compensate. The problem with buying cams for these engines, most people that have them won't break up the set. Maybe you should ask your builder about splitting the cost on a set of Schrick camshafts. Then you could bump the duration and run with split duration. Use the M88/3 264 cam on the intake side and run a 272 on the exhaust.

And as rcbmw has stated, you first need to know what you currently have.

Good Luck.

Rich

Post by **mooseheadm5** » Jun 24, 2009 11:34 PM

Adjusting the valves is a trivial matter. The shims are about $4 each and sometimes you can just switch them around. Volvo shims tend toward being thicker and should easily compensate for any change in base circle. The engine has solid lifters, which is why you must adjust the valves in the first place. You should find out which cam you have to begin with. No matter what you do, if you replace the intake cam, you will have to adjust the valves on the intake side again.

wkohler · Post by **wkohler** » Jun 24, 2009 11:44 PM

Volvo shims don't have those sweet chamfered edges, though.

gcracker · Post by **gcracker** » Jun 25, 2009 12:12 AM

rcbmw wrote: The M635CSi M88/3 engine uses a 264° cam that has a smaller base circle (-1mm) than the camshafts found in the S38-B35 or B36. Given this, I would confirm which cam your engine has.

Best,
RCBMW

Ok, who wants to help me do that? I know they look very different from my originals... and have "8898" stamped on them. I have pictures, and can take more.

gcracker · Post by **gcracker** » Jun 25, 2009 12:16 AM

mooseheadm5 wrote:Adjusting the valves is a trivial matter. The shims are about $4 each and sometimes you can just switch them around. Volvo shims tend toward being thicker and should easily compensate for any change in base circle. The engine has solid lifters, which is why you must adjust the valves in the first place. You should find out which cam you have to begin with. No matter what you do, if you replace the intake cam, you will have to adjust the valves on the intake side again.

I'm not afraid of doing the adjustment, but my engine felluh has the pucks on hand so...

I wonder if they're the volvo shims, too, since the new-looking ones lack any chamfered edges.

gcracker · Post by **gcracker** » Jun 25, 2009 12:44 AM

Rich Euro M5 wrote: ... Now if your valve stems were cut in length to compensate for the smaller base circle of the M88/3 cams, you'll might need to find one as a replacement, I don't know if there's enough adjustability in the shim sets to compensate.

Rich

Therein lies the dilemma. This cam tray was sold to me to replace my spent one. I was told it was from an M6, cut it could've been an M635, too. The valve stems appear to have been trimmed, so I will likely need to stay with the M88/3 cam if that is what I have. It is entirely possible that the shop that originally messed up my head work just decided to cut the stems instead of sourcing the shims. I assume, however, that the reason they were cut is because the base circle is smaller.

Who can give me some identifying marks to help me with this problem?

Or, I can link to pics:
Damaged nose-
http://bimmerboard.com/members/gcracker ... damage.JPG
See the burr?
http://bimmerboard.com/members/gcracker ... geshim.JPG
Two pics of the lobes:
http://bimmerboard.com/members/gcracker ... l/m88a.JPG
http://bimmerboard.com/members/gcracker ... l/m88b.JPG
And one of the two style shims installed:
http://bimmerboard.com/members/gcracker ... oshims.JPG
Boy, do I wish this never happened:
http://bimmerboard.com/members/gcracker ... amslam.jpg

EDIT:
Leo from R&L Engine called and confirmed the need to replace the camshaft.
I gave him casting numbers from the tray, but we are not hopeful about finding the right part easily.
And since I can't say for sure what I've got...

Devinder · Post by **Devinder** » Jun 25, 2009 10:55 AM

I can ID the cam if you measure the width (approximation of base circle) and height of the lobe (base circle + max lift). I have a spare S38b35 cam.

Rich Euro M5 · Post by **Rich Euro M5** » Jun 25, 2009 12:40 PM

gcracker wrote:
Rich Euro M5 wrote: ... Now if your valve stems were cut in length to compensate for the smaller base circle of the M88/3 cams, you'll might need to find one as a replacement, I don't know if there's enough adjustability in the shim sets to compensate.

Rich
Therein lies the dilemma. This cam tray was sold to me to replace my spent one. I was told it was from an M6, cut it could've been an M635, too. The valve stems appear to have been trimmed, so I will likely need to stay with the M88/3 cam if that is what I have. It is entirely possible that the shop that originally messed up my head work just decided to cut the stems instead of sourcing the shims. I assume, however, that the reason they were cut is because the base circle is smaller.

It's easy to tell which type of cam tray you have by the location of the oil fill cap. The M88/3 engine used in the Euro M635CSi and Euro M5s has a narrow cam chain channel and the oil fill cap is located between cylinders 1&2 on the valve cover. The later S38B35 cam tray has a wide cam chain channel with the oil fill cap located directly above the cam chain.

Unfortunately this doesn't tell you anything about the type of camshaft. Did your new to you cam tray include the camshafts, and did the seller indicate they were 248 degree cams ? If so you have S38B35 cams.

If you acquired 264 degree M88/3 or Schrick cams separately from the cam tray, then you need one of those. But your title indicates you need a 248 degree camshaft and this duration wasn't offered in the M88/3 engines.

Rich

rcbmw · Post by **rcbmw** » Jun 25, 2009 1:28 PM

If the shop was not able to provide detailed information about the parts its unlikely they would have known to source obscure M88/3 bits such as the cam tray and shafts. I suspect this car has the car has the original 248° camshafts that were taken from an M6 (NOT M635CSi).

Best,
RCBMW

gcracker · Post by **gcracker** » Jun 25, 2009 9:22 PM

Rich Euro M5 wrote: It's easy to tell which type of cam tray you have by the location of the oil fill cap. The M88/3 engine used in the Euro M635CSi and Euro M5s has a narrow cam chain channel and the oil fill cap is located between cylinders 1&2 on the valve cover. The later S38B35 cam tray has a wide cam chain channel with the oil fill cap located directly above the cam chain.

Unfortunately this doesn't tell you anything about the type of camshaft. Did your new to you cam tray include the camshafts, and did the seller indicate they were 248 degree cams ? If so you have S38B35 cams.

If you acquired 264 degree M88/3 or Schrick cams separately from the cam tray, then you need one of those. But your title indicates you need a 248 degree camshaft and this duration wasn't offered in the M88/3 engines.

Rich

If the timing cavity was smaller, it wouldn't bolt up, right? My new (to me) cam tray looks exactly like my old one, except someone scraped off the vin sticker (damnit). As for the valve cover, I kept my old one and don't have any other. As for the shafts, yes, they were installed in the tray when purchased. The source was Rick Stormer of Covered Bridge BMW in NH. He sourced them from somewhere around, but I don't know where. He said it was form an M6, but I don't know if he was 100%. As for my post title, I assumed they were 248, 1) because I didn't realize the M88/3 shafts were 264 and 2) because I was told they came from the M6, which usually had the S38.

The shaft you have pictured here: ( http://e28-535i.com/upload/Head.JPG ) looks like mine and has the same narrower lobe as compared to the base circle.

gcracker · Post by **gcracker** » Jun 25, 2009 9:24 PM

rcbmw wrote:If the shop was not able to provide detailed information about the parts its unlikely they would have known to source obscure M88/3 bits such as the cam tray and shafts. I suspect this car has the car has the original 248° camshafts that were taken from an M6 (NOT M635CSi).

Best,
RCBMW

Do my pictures help at all?

I thought that since in this thread ( http://www.mye28.com/viewtopic.php?prin ... viewresult ), where Raymond (aplinab10biturbo) mentions that the M88/3 had smaller, assymetrical lobes, that was my ticket.

gcracker · Post by **gcracker** » Jun 25, 2009 9:31 PM

Devinder wrote:I can ID the cam if you measure the width (approximation of base circle) and height of the lobe (base circle + max lift). I have a spare S38b35 cam.

I don't have any calipers or mics at home, but with an adjustable (crescent) wrench, I get 34mm base circle and then approximately 10.5mm of lift. That 10.5mm has a .4mm margin either way, I'd say.

Rich Euro M5 · Post by **Rich Euro M5** » Jun 26, 2009 2:48 AM

gcracker wrote:
Rich Euro M5 wrote: It's easy to tell which type of cam tray you have by the location of the oil fill cap. The M88/3 engine used in the Euro M635CSi and Euro M5s has a narrow cam chain channel and the oil fill cap is located between cylinders 1&2 on the valve cover. The later S38B35 cam tray has a wide cam chain channel with the oil fill cap located directly above the cam chain.

Unfortunately this doesn't tell you anything about the type of camshaft. Did your new to you cam tray include the camshafts, and did the seller indicate they were 248 degree cams ? If so you have S38B35 cams.

If you acquired 264 degree M88/3 or Schrick cams separately from the cam tray, then you need one of those. But your title indicates you need a 248 degree camshaft and this duration wasn't offered in the M88/3 engines.

Rich
If the timing cavity was smaller, it wouldn't bolt up, right? My new (to me) cam tray looks exactly like my old one, except someone scraped off the vin sticker (damnit). As for the valve cover, I kept my old one and don't have any other. As for the shafts, yes, they were installed in the tray when purchased. The source was Rick Stormer of Covered Bridge BMW in NH. He sourced them from somewhere around, but I don't know where. He said it was form an M6, but I don't know if he was 100%. As for my post title, I assumed they were 248, 1) because I didn't realize the M88/3 shafts were 264 and 2) because I was told they came from the M6, which usually had the S38.

The shaft you have pictured here: ( http://e28-535i.com/upload/Head.JPG ) looks like mine and has the same narrower lobe as compared to the base circle.

At least you know you have a cam tray from the S38B35 engine. I don't believe I would trust written descriptions of the cams without having a photo of the camshafts sitting side by side to illustrate the differences.

Rich

gcracker · Post by **gcracker** » Jun 26, 2009 9:12 AM

Rich Euro M5 wrote:
At least you know you have a cam tray from the S38B35 engine. I don't believe I would trust written descriptions of the cams without having a photo of the camshafts sitting side by side to illustrate the differences.

Rich

By pictures, you mean the ones I linked to aren't enough? What pics do you need to identify?

Rich Euro M5 · Post by **Rich Euro M5** » Jun 26, 2009 11:32 AM

gcracker wrote:
Rich Euro M5 wrote:
At least you know you have a cam tray from the S38B35 engine. I don't believe I would trust written descriptions of the cams without having a photo of the camshafts sitting side by side to illustrate the differences.

Rich
By pictures, you mean the ones I linked to aren't enough? What pics do you need to identify?

What I mean is that you have a S38B35 intake cam sitting next to a M88/3 camshaft in a photo. I doubt you could discern the difference in base circle from a photo, 1mm is too small unless you have a large, high resolution photo with reference marks. From an end view you might be able to tell. Ditto for the cam lobe shapes, you'd need an end view of the cams side by side.

The photo of my head only shows the very end of both camshafts in an oblique view. There's not enough there to tell what your looking at if you didn't know what it was.

Rich

rcbmw · Post by **rcbmw** » Jun 26, 2009 5:25 PM

Rich has shared some great feedback. Its unlikely that you will find the camshafts individually and should you purchase a complete set, you will not need to identify which camshafts are currently fitted. I am still under the impression that you have the original 248° camshafts. Rick Stormer is knowledgeable and also owns an M635CSi. He should be aware of the differences in specs.

Best,
RCBMW

photopark · Post by **photopark** » Jun 26, 2009 8:02 PM

The M88/3 intermediate housing would not fit on the S38 head.

Your S38b35 Valve cover would not fit on a M88 intermediate housing.

Mic the shims.
M88 = 31mm diameter
S38 = 33mm diameter

PM me if you need S38b35 camshafts.

Doug

gcracker · Post by **gcracker** » Jun 26, 2009 10:46 PM

To clear up some stuff:

I realize my head/tray are not from the M88/3. (Thank you, forgot the timing cavity)
I am unsure of the ID on the camshafts.
The only reason I care about the ID is that I need one.
I need one, because one is quite toast.
I don't care what cam I replace it with for any reason other than I want to drop it in and not worry about re-adjusting valve clearances.
I don't want to readjust the valves because I already mounted the head to the block and the tray to the head.
If I remove them to perform the adjustment, I am throwing away a head gasket and 14 head bolts.

Everyone replying has been very helpful, and I appreciate it. Thank you.

I'm not sure, though, why everyone is saying to buy a set of shafts in the first place. (I have found members willing to sell a single to me.)
It's my understanding that several folks here run mismatched camshafts on purpose, like 248/264 or 264/272 or the schrick 272/280.
I also realize that by some of my questions, I don't paint a picture of a knowledgeable or qualified technician. Maybe I'm not. I certainly admit not knowing a fraction of the lore that most of the members here possess. I am, however meticulous and patient.
I have waited for four years to get this engine back in its home. Finally, two days before I planned to drop it in, I noticed this awful failure.
I want to fix it the right way, but I want to make sure I am not throwing money (and anxious time) away by disassembling if it can be avoided.
If not, I will do what I must. (Leo wants to evaluate the head now, anyway... convinced I did something wrong.)

Rich,
I apologize for thinking you could identify the camshafts from a picture. I thought that all B35/B36 cams had the same full-width lobes in relation to the base circle. I likewise assumed that the M88/3 cams were assymetrical, and so I assumed (based on assumption) that my cams (not the tray anymore) was from the M88/3. I never thought you'd be able to tell me what duration/lift they were, just maybe the S38 vs. M88 origins. Thank you for trying to indulge me. I promise: I am growing from this experience!

RCBMW,
I would love to get back in touch with Rick, but last time I spoke with him, his Dr. had told him to take a long vacation. I never heard from him after that. Do you know if he still runs his shop in Conway? He could probably clear this up for me.

Please understand, if I seem frustrated, it's not at any members or their responses to my posts. ALL posts help me. I am only frustrated because I thought I would hear my baby run this Sunday.

Thank you all!

-Graham

P.S. Does this picture help? I can't cross this number.
That's all there is... 1.308.691.9

Post by **mooseheadm5** » Jun 26, 2009 11:51 PM

Now I see why you are worried about the valve adjustment. Just thought you should know that adjusting the valves only requires a tappet depressing tool, a set of feeler gauges, maybe a micrometer, and a magnet. You absolutely do not need to pull the head at all, so don't worry about that. It does not matter which cam you use, it is likely that you will need to change the clearance of at least one valve because the cam may have worn a tiny tiny bit different from your original. It is nothing to worry about. Shims cost $4 from International Auto Parts (Fiat shims.) It takes about two hours for me to clean everything and adjust all the valves.

photopark · Post by **photopark** » Jun 27, 2009 12:14 AM

S38b35.

Rich Euro M5 · Post by **Rich Euro M5** » Jun 27, 2009 7:58 AM

Graham,

The reason some run split cam timing is to improve exhaust scavanging. The same thing to a lesser effect can be done by changing the gear on the exhaust cam. Most people install the S14 EVO gear, because it's much easier and less expensive than swapping out a camshaft. So if you have one S38B35 cam, you could install a S38B36 cam on the exhaust side and you'd be running the 248/264 combo.

Rich

gcracker · Post by **gcracker** » Jun 27, 2009 9:15 AM

mooseheadm5 wrote:Now I see why you are worried about the valve adjustment. Just thought you should know that adjusting the valves only requires a tappet depressing tool, a set of feeler gauges, maybe a micrometer, and a magnet. You absolutely do not need to pull the head at all, so don't worry about that. It does not matter which cam you use, it is likely that you will need to change the clearance of at least one valve because the cam may have worn a tiny tiny bit different from your original. It is nothing to worry about. Shims cost $4 from International Auto Parts (Fiat shims.) It takes about two hours for me to clean everything and adjust all the valves.

I was mostly worried about the adjustment thinking that I had a smaller base circle, and putting the larger one on would mean my valves might not be closed... and my pistons already climb higher than OEM. I tend to worry overmuch about this car.

I have learned that when given two choices, worrying more keeps engines in one piece. If you recall my greeting post, I almost didn't do this rebuild when I did and I would've been driving with no crank nut!

gcracker · Post by **gcracker** » Jun 27, 2009 9:22 AM

photopark wrote:S38b35.

Indeed! That clears that up!

gcracker · Post by **gcracker** » Jun 27, 2009 9:28 AM

Rich Euro M5 wrote:Graham,

The reason some run split cam timing is to improve exhaust scavanging. The same thing to a lesser effect can be done by changing the gear on the exhaust cam. Most people install the S14 EVO gear, because it's much easier and less expensive than swapping out a camshaft. So if you have one S38B35 cam, you could install a S38B36 cam on the exhaust side and you'd be running the 248/264 combo.

Rich

Back when I began this project, I purchased that gear along with a Dinan Gen I chip from either Todd Kenyon or Andrew Elmore... I can't remember.
I did install it in this rebuild, but am not sure if I'll keep it for long.
I am seriously considering running the b36 cam, since I need one anyway, but $500 for one, ouch.

I still have this nagging concern: Why are some cams full-width on the lobe and others are half or less and assymmetrical?
I need to have Leo measure these cams and put an end to all this confusion. I'm sure he can tell me all the specs.

gcracker · Post by **gcracker** » Jul 16, 2009 7:59 PM

Here is proof that my cam is a standard duration U.S. Camshaft.

MyE28.com

MyE28.com

Renamed: Camshaft identification help???

Renamed: Camshaft identification help???

I can put my fears to rest.