79 Darmah Project

mizike77 · Post by **mizike77** » Tue Dec 02, 2008 7:35 pm

Well , I am planning on starting my winter project soon. I have a 79 SD that sat in a basement for 20+ years. Mostly complete, with some goodies...40mm Delorttos, with matching intakes, 2 into 1 pipe, drilled discs. Iam starting w the engine first. Mostly to see if its worth rebuilding and putting money into. The engine is siezed...not sure if its stuck or if its blown. A light in the cylinders when I first got it revealed surface rust , so I filled the cylinders up w mystery oil and let it soak. Its been a few months now and I took a look in the other night and saw that the top cylinders oild had drained but the front cylinder is still holding fluid. So this weekend I am going to take the front head off to get a closer look.
Are these early SDs prone to crank failure? Is there anything tricky about taking the heads and possibly jugs off a bevel engine? Im of average mechanical ability. Have had lots of bikes in the past that I had maintaned and repaired but have never worked on a Ducati engine.......especially a bevel head. I must say, Im a bit nervous that im going to break or lose something, or not know how to put it back together!

cafe*racer · Post by **cafe*racer** » Tue Dec 02, 2008 9:03 pm

I would buy this manual from Steve in the 'shop' area if you do not have it: http://shop.bevelheaven.com/detail.aspx?ID=614 Sometimes you can find old Haynes manuals that have good not technical language and processes. Not sure if they made one that covers the Darmah. As far as dis-assembly, depending on how far you go, there are a few things to keep in mind: mind how your gears are positioned for timing, keep track of shim placement (they are everywhere), take pictures and don't lose anything, MOST IMPORTANT: if you get stuck call a professional. You should be ok just pulling a head and barrel, so go for it.

Craig in France · Post by **Craig in France** » Wed Dec 03, 2008 1:33 am

mizike77 wrote: <snip>
I took a look in the other night and saw that the top cylinders oil had drained, but the front cylinder is still holding fluid.

A common problem with engines that have been left, I'm afraid. Because of the inclination of the front cylinder, condensation inevitably collects around the piston and the rings rust in the bore.
If you have the time, don't rush anything - you don't want to add to your problems by breaking any of the fins of the barrel, for example. Keep going with the easing oil - I know Steve A. swears by Kroil, btw. A few 'heat-and-cool' cycles may help too. You could take the engine out of the frame to do this, of course, allowing you to get on with the restoration of the cycle parts. If you're lucky, the piston may be reusable, with a new set of rings; but the cylinder liner will most likely be US, I'm afraid.

mizike77 wrote: Are these early SDs prone to crank failure?

Crank failure is much more related to how the engine has been cared for, especially the frequency of oil changes, than the age of the bike (and '79 isn't particularly early, btw; Darmahs first appeared in '77). But after 20 years of being stood, and with no knowledge of the bike's history - well, frankly, IMHO you're into a crank strip, anyway. It's expensive, but you don't want to go thru a partial re-build only to discover the crank is toast. And the only way to properly check a roller bearing big end is to strip it and visually inspect it.

mizike77 wrote: Is there anything tricky about taking the heads and possibly jugs off a bevel engine?

There's nothing especially complicated about these engines (except, possibly, setting a zero clearance on the closing rocker

). Work clean, work tidy, check everything against the factory tolerances, don't loose the shims, don't force anything etc. But, that said, there's never any substitute for years of experience, i.e. people who know the peculiarities of the engine and how to make apparently minor improvements which have a major impact on the quality of the re-build.

As always, it comes down to how deep are your pockets and what are you trying to achieve?

HTH.

Craig

Per Garbos · Post by **Per Garbos** » Thu Dec 04, 2008 5:21 am

My bevel had been standing for many years before I got it.
At first the engine was running perfect but soon after (50-100 km) a noise from the big end was appearing.
When i took the engine apart, i found small grooves from corrosion in the inner and outer rings of the main bearings - especially where the balls had been for those years.
Even it was difficult to see at the big end ( the surface was completly destroyed) I am quite sure it was started because of corrosion, mainly because the bike had only been running 20.000 km from new.

A couple of year, standing with old oil can be very harm full.

Best Regards Per Garbos

mizike77 · Post by **mizike77** » Thu Dec 11, 2008 5:13 pm

My slow progress to date. The front cylinder is way stuck in the barrel. Got the head off and there is lots of rusty goo everywhere... Any suggestions on how to get the stuck barrel off?

pics...
http://picasaweb.google.com/mizike77/DarmahTeardown#

cafe*racer · Post by **cafe*racer** » Thu Dec 11, 2008 9:04 pm

Do you mean the piston is stuck in the cylinder? Or do you have the barrel and cylinder(liner) free from the case?

Post by **BevHevSteve** » Fri Dec 12, 2008 9:49 am

mizike77 wrote:My slow progress to date. The front cylinder is way stuck in the barrel. Got the head off and there is lots of rusty goo everywhere... Any suggestions on how to get the stuck barrel off?

pics...
http://picasaweb.google.com/mizike77/DarmahTeardown#

pour some KROIL into the cylinder. Have your dropped the engine yet? If yes, tilt it so you can pool the kroil all the way around. THen put a piece of seran wrap inside to keep it from evaporating fast. Let it sit for a few days.

Heat is your friend from a heat gun, not a torch.....

Assuming you have the other cylinder out, then get a wooden dowel like a curtain rod, and give her some taps with a mallet

mizike77 · Post by **mizike77** » Fri Dec 19, 2008 2:07 pm

Thanks for the tips guys. The motor is coming out this week, so I can tip it up to try to get some oil on top of that front cylinder.. Havnt been able to work on it at all this past week. We had a black out here in NH. Just got my power back today after 8 days!

mizike77 · Post by **mizike77** » Sat Dec 20, 2008 6:08 pm

Dropped the engine today. Have it tipped up so the front cylinder can soak untill after the holidays... Todays pics...sorry for the blurry ones, my camera is rather old!

http://picasaweb.google.com/mizike77/Da ... yecRYWJMUA#

Post by **BevHevSteve** » Sun Dec 21, 2008 5:34 pm

don't worry about blurry photos, just keep em coming. Let us know how things pan out after a few daze of soaking....

mizike77 · Post by **mizike77** » Mon Dec 29, 2008 3:28 pm

Today brought some progress. Built a crappy engine stand that worked well. Pulled the rear head off wich took a lot more strength than the front did. The rear cylinder is in much worse shape than the front was. Lots of rust. Try as I might I could not get the jug off. Heat, hammer and dowl,and half donkey piston pusher wouldnt do it. The good news is the craNK turns freely and the lower end looks rust free and clean. The under side of the rear head has the words "Johnson Eng. Tech. 21 sept 95" had engraved in it. So turns out my motor has been out before and most likley has some work done to it. My pistons have AE cast into the bottom and the top reads 86-66712/c.Dont know if thats stock or not. Also under the piston is hand scribed 0 on the intake side and 2 scribed on the exaust side. Dont know what all this means but maybe some of you do. Here are todays photos.

http://picasaweb.google.com/mizike77/Da ... JqE2zQRJJw#

mizike77 · Post by **mizike77** » Tue Jan 06, 2009 4:56 pm

Finally got the top jug off tonight. Took me a couple weeks and lots of different home made pullers and pushers. Heat, mystery oil, pb blaster and kroil all went into it. In the end it was a puller and force that got it off. Unfortunatley I broke a fin off in the process. .......

lomax · Post by **lomax** » Mon Jan 26, 2009 1:57 am

Respect for your work - looks like the basement holding your SD for 20+ years was flooded......

now I am afraid to get my SD out of the garage, where it was stored for about 12 years. The only things I did for storage was to drain the carbs, fill up the tank and lift the wheels. I turned the engine every other year by hand and I put some sealing spray into the cylinders (same stuff as is used for diecast moulds).

I wonder, if my engine looks fine or has to be unscrewed and rebuild too...

ALinHB · Post by **ALinHB** » Mon Sep 21, 2009 11:23 am

Hi Mizike77

There is a site on the internet has has a pdf version for sd Darmah 900 manual for free. I was using this untill i found a Hayes hard copy manual on New Zealand's Trade Me site. The Hayes manual is far superior and has trouble shooting. Also on www.trademe.co.nz a guy sells copies of ducati manual's there but not hayes.

Look at this site for a free download.
http://www.ducatimeccanica.com/darmah_9 ... /index.htm
Al

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79 Darmah Project

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