Head rebuild and rings?

[weasel01]

I have some oil leaking from my pushrod tube boots and I have some oil sweating on to the block at the bottom of my cylinders.

Eventually I will correct this but wondered if when I'm that deep in should I go ahead and replace rings valves valve seats etc?

Wondered if this is doable by a guy like me or should I send the heads off to be done?

[Bob_Roller]

I'm not sure if by '83, that BMW had corrected the valve seat problem or not .

Do a compression check, and see what kind of results you get .

I don't know if you have had the exhaust system off or not, but if you ever do, rotate the engine until you get the exhaust valves open, then you can get a good look at the valve faces .

It's probably best to send the heads out for seat changes, there are a few repair shops that specialize in airhead cylinder over haul .

[Bengt_Phorqs]

Pushrod seals can be done with a minimum of hassle.  I believe there was thread here in the last six months or so.  Before pulling the heads and doing a full valve job, what is the compression reading on each cylinder?

[weasel01]

I've wondered about compression, I'll buy on of those guages and see.

The only thing that makes me wonder about my heads is at a cold start up the left side exhaust valve area is rattley sounding till it warms up then it's sounds very good and quiet...maybe that's normal but maybe not.

Thoughts?

[weasel01]

also...whats a head job cost these days?

[Justin B.]

I don't think the valve seat issue was resolved until 1985 or so and a couple years later on the 1000cc bikes when they were re-introduced.  

[Bob_Roller]

Sue and Rob V. just had their cylinder heads  'overhauled' in the last year, so they could probably give you the latest costs .

[Lucky_Lou]

Pushrod seals can be done with a minimum of hassle.  I believe there was thread here in the last six months or so.  Before pulling the heads and doing a full valve job, what is the compression reading on each cylinder?

+1 i dont know what millage you have but i wouldnt do the valve seats unless i had too, Motorworks and motobins offer head overhauls but i think there quite expensive.
lou

[weasel01]

Well,

I'm gonna need to pull the jugs anyway to replace the gaskets that are leaking against the block and thought it would'nt be that expensive?

Is there machining involved? why is it so expensive?

[nhmaf]

The head work needs to be done by a good machinist who has worked on these heads before - the old valves get taken out and the old valve seats must be removed.  The new seats must be properly installed and may require some careful machining to get them properly fitted, and the valves seats must be cut properly for the new valves to seat well on them.   The new valves also require new valve guides to be installed, depending on the valves used, this may require some careful reaming/honing of the guide holes.    Black diamond valves are a popular replacement, but the general consensus is that the OEM BMW valves (which are of course, more expensive) are preferred by many.

All this work takes time to do properly, and it will typically run in the $500 vicinity to do, depending on geographic location, # of middle men, time of year/workload, etc.   Someone was selling a refit seat of R65LS heads on ebay for $650 that I was watching for some time, but I didn't pull the trigger on it.   Figured that I'd wait until I say the valve lash closing up - or at least until business is better - before spending the do-re-mi at this time.

[montmil]

Just read the ad in ABC's Airmail for Motor Works cylinder head refurbishing. They offer five-day turn at $195.00 plus shipping. Kicker is valves and seats, if required, are extra cost.

http://motorworkspromach.com/

Their website does not list the details but their Airmail ad does. Here tis:

• Bead blast heads
• Recut valves
• Recut seats w/ triple grind
• Replace valve guides w/ BMW components
• Install stem seals
• Leak down test w/ written results
• Valves & seats, if req'd, at extra cost. BMW factory stock parts.

I have no experience with this outfit.   Monte

[weasel01]

Just read the ad in ABC's Airmail for Motor Works cylinder head refurbishing. They offer five-day turn at $195.00 plus shipping. Kicker is valves and seats, if required, are extra cost.

http://motorworkspromach.com/

Their website does not list the details but their Airmail ad does. Here tis:

• Bead blast heads
• Recut valves
• Recut seats w/ triple grind
• Replace valve guides w/ BMW components
• Install stem seals
• Leak down test w/ written results
• Valves & seats, if req'd, at extra cost. BMW factory stock parts.

I have no experience with this outfit.   Monte

I think Bob_roller had a bad experience with them? It's referenced in the credit card thread....

[Bengt_Phorqs]

Send a note or call Bruce Davidson at Boxers By Bruce.  Bruce is usually pretty reasonable and does quality work.  I believe his website is www.boxerbruce.com

[CE144]

I also had leaky PR seals and a relatively high mileage bike (70,000 miles).

Looking to make this a long-term repair, I pulled the jugs and sent the heads to Ted Porter at The Beemer Shop in Scotts Valley, CA.  He does excellent work, but be prepared to wait.  I sent the heads to him in April and got them back in July.  The price including valves, springs, guides, a helicoil for the spark plug hole wasn't cheap... he'll give you a ballpark by email before you ship and then a detailed quote once he does a thorough evaluation.  

Other good options for this service are Oak in IL and Tom Cutter in PA.  If you don't already have it, gets Oak's top end manual... a great resource unless you are already comfortable with taking all this stuff apart and getting it back together again.

I also cleaned up the pistons and cylinders and put on new rings.  

Chas Gross
Ellington, CT
1987 R65

[ambrose78]

Are there any signs of iminent head failure?

Or even if there is a way to tell if the  head work has been done by a previous owner?