Author Topic: Head Removal. To proceed or not to proceed (Read 37146 times)

Tyler S · « **Reply #50 on:** March 02, 2016, 16:47:53 »

Dan, Absolutely!

Thanks Pinder, I have a tube of thread sealer on hand. Will do the manifold studs in addition to the ball stud bases.
Tyler

Tyler S · « **Reply #51 on:** March 02, 2016, 23:48:02 »

So with everything else going on I forgot to check ALL the camshaft bearings. The end ones looked good so I didn't see this until yesterday.

New camshaft on order from Germany. None in the states. New bearings were available here.
I'm thinking with the warped head that it was overheated at some point. The head is warped up in the middle so it took out the center camshaft bearings. The gouge is too deep to repair with a new grind and undersize bearings.
Pandoras Box strikes again.

Benz Dr. · « **Reply #52 on:** March 02, 2016, 23:57:01 »

That's a tough one and it's not all that common either. Most damaged cams have bad lobes but the main journals generally remain intact.

Is the cam junk or can it be saved?

Tyler S · « **Reply #53 on:** March 03, 2016, 00:10:50 »

Dan, there is almost a 1mm deep groove gouged out of the journal on #3 so I'd say its junk. Too bad because the lobes are almost perfect. I already have a new set of standard size bearings so even if it could be repaired I would need another set of undersize. Oh, Well. I'll keep the old one for garage art.

Pinder · « **Reply #54 on:** March 03, 2016, 01:41:47 »

Tyler,

When I adjusted the valves. I found that one of my lobes (exhaust) has some were. I was thinking of replacing the cam but as the car seems to run ok. I may defer to a later time. How much is the new cam? I could not find one in the states. I was considering getting it splatter welded and re ground. Ive asked for estimates and will post prices. For now as its the cam and relatively easy to swap out Ill run the car as is.

Tyler S · « **Reply #55 on:** March 03, 2016, 02:00:57 »

Pinder, I wish it was just a bad lobe. That only runs a couple hundred to repair. If they re-grind your cam after the repair, I wonder if they could put the 09 "hot cam" profile on it! This new cam just under $700 including shipping. Don't have an invoice yet so not sure how much of that was the cam itself.(taxes, shipping etc) Yes, none in the states. Germany has 57 of them! Keep in mind this is for a 250sl. Your price may vary for application. You may also need to replace the rockers and the cam bearings. I wouldn't run a new cam on old bearings or rockers.

ja17 · « **Reply #56 on:** March 03, 2016, 04:54:48 »

Those Camshaft journals are not under a lot of load. The groove should have no consequence as long a the bearing is good and the cam journal is up to specs. A lot of the early cams had a deep grooves cut into the journals from the factory. Of coarse new is always best unless you need the $700.00 somewhere else!

Tyler S · « **Reply #57 on:** March 03, 2016, 07:18:55 »

Joe, this is definately not a factory groove. Its so bad that the groove sides had mushroomed up eating into the bearing. I had to heat the bearing just to get it off past this lip that was created. I thought about a used cam but theres just no way to know what condition you will get. I already have a new set of bearings and rockers so a new cam just makes sense at this point. Putting the 700 into new squareweave carpet woulda been nice! $:-\$

ja17 · « **Reply #58 on:** March 03, 2016, 15:02:52 »

Yes, I can see that is not a factory groove. Unfortunately it sounds like the cam bearing was damaged beyond use. Build up on the cam journal itself can be cleaned off by in a lathe, but if it is undersize then you have problems. New rocker arms are recommended when installing a new cam (ouch $) if new rockers, then new ball adjuster studs and pressure pads also (ouch $$). In most cases the good used rockers etc. will work fine. Inspect them closely.

Tyler S · « **Reply #59 on:** March 03, 2016, 17:21:28 »

With all the other new parts I have collected over the past 2 years, the only things being re-used on the head are the inner springs, rotators, and valve seats. Other than the cam and bearings, the rest of the old parts are in good shape. But since I have new, why not use them.

ja17 · « **Reply #60 on:** March 03, 2016, 22:55:27 »

Yes, you can't go wrong with new!

Tyler S · « **Reply #61 on:** March 04, 2016, 23:24:19 »

Picked the head up today. Final thickness after straightening and machine work is 84.5mm Have almost everything ready to re-assemble. New cam bearings, rockers, ball studs, ball stud spring clips, all sprockets, chain, tensioner arm pin, valve thrust pieces, oiler tube, and other misc parts. A set of .30mm (.0118in) cam tower shims are on the way to make up for the .012in (.006 on each side) the head was surfaced. Camshaft should be here next week. Sure does look pretty right after machining.

I learned somthing new today. The machine shop knurls the top outside part of the valve guide to keep the valve stem seals from slipping off! Gives them somthing to grab on too.

66andBlue · « **Reply #62 on:** March 05, 2016, 04:39:33 »

Quote from: Tyler S. on March 04, 2016, 23:24:19

.... The machine shop knurls the top outside part of the valve guide to keep the valve stem seals from slipping off! Gives them somthing to grab on too.

Can you posy a photo please?

Tyler S · « **Reply #63 on:** March 05, 2016, 05:50:52 »

Sure Alfred, I hope these can be seen. It's hard filming with a potato.

erickmarciano · « **Reply #64 on:** March 05, 2016, 14:49:13 »

Got a question
If we know how much was cut from original thickness can we determine the shim needed for the cams? How about the spring spacers?

Thanks for a great post

Pinder · « **Reply #65 on:** March 05, 2016, 15:25:10 »

Looks really good.

Tyler S · « **Reply #66 on:** March 05, 2016, 16:30:02 »

Erick, yes you would want to use a shim or a combination of shims closest to the measurment of total thickness of the head removed. In my case .012in was removed so I ordered .0118 (.30mm) shims. The valve thrust shims are a little different. The valves in my case were replaced, however the original seats were ground. There is a spec in the bbb for determining stem height v.s thrust piece measurment. In my case, 3.5mm thrust piece vs the stock 4.5 will be used. You need to take into account the cam shims being added to this measurment because the cam sits higher off of the resurfaced head.

erickmarciano · « **Reply #67 on:** March 05, 2016, 17:11:04 »

Thanks
Where can I find these cam shims?

Tyler S · « **Reply #68 on:** March 05, 2016, 17:36:55 »

Quote from: erickmarciano on March 05, 2016, 17:11:04

Thanks
Where can I find these cam shims?

Metric Motors. Listed in the "suppliers" list here.

erickmarciano · « **Reply #69 on:** March 05, 2016, 21:20:07 »

did you shim under the springs?

Tyler S · « **Reply #70 on:** March 06, 2016, 02:03:02 »

No, If its out of spec you would need to replace the seats as well as the valves.

Tyler S · « **Reply #71 on:** March 10, 2016, 00:55:57 »

FedEx dropped off the new camshaft today. It's a lot more refined than the old one. There is no rough casting area between lobes. This thing is ready to go back together. Busy painting the block and chasing threads with a tap, nothing too exciting. Next post will be with the head married to the block.
Tyler

Tyler S · « **Reply #72 on:** March 10, 2016, 23:38:32 »

Making headway. Head and camshaft installed. Looks great with all new parts. Too bad the valve cover hides it all.

kampala · « **Reply #73 on:** March 11, 2016, 05:34:03 »

Looks fantastic. Now you will have to make a "clear" valve cover or at least a viewing port.

Appreciate the updates.

mbzse · « **Reply #74 on:** March 11, 2016, 07:40:17 »

Quote from: Tyler S.

Making headway. Head and camshaft installed.../...

Nice to see your fine head refurbish work... thanks for sharing
/Hans in Sweden

News:

Author Topic: Head Removal. To proceed or not to proceed (Read 37146 times)