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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 12:40
by maxstu
itchyfeet wrote:^^^^ thats quite common hammered by a bad tappet, I wouldn't worry you are not building a race engine just got to get a runner.

Check associated push rod roll on glass.. Its not distorted

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 12:58
by maxstu
Cases apart eventually. Always check for a missed case bolt. I missed two :oops:

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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 12:59
by itchyfeet
tappet(hydraulic lifter) may be shagged or maybe it had a duff tappet years ago before the last rebuild.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 13:01
by maxstu
itchyfeet wrote:tappet(hydraulic lifter) may be shagged or maybe it had a duff tappet years ago before the last rebuild.

Will check lifters and valves later.
Ornamental camshaft anyone? Where do l go with this

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And where it mates with crank. Noted two teeth edged in blue parker pen minor damage. Hence why engine locksxwhen they mesh. Not good me thinks.

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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 13:14
by itchyfeet
need to find out why that happened did some debrig get in the gears.
as a minimum the gear needs swapping, does the cam look reasonable?
cams were available with a varity of gear sizes to set backlash but in reality as long as the new cam/gear is not tight it will be ok just a bit noisier. Aircooled have one gear size only so no chance to adjust backlash.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 13:16
by itchyfeet
crank gears are available but quality low, sometimes needs must but a second hand crank gear may be better than new.

I have a crank gear puler you can borrow, 50 quid to buy.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 14:22
by maxstu
Thanks Paul, l have a spare crank indoor. Camshaft lobes look okay to the eye..yet badly pitted elsewhere. Now l need to start measuring specs on components.

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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 14:29
by maxstu
Previously owner had a massive backfire through pancake and melted carb into engine. I bought as a none runner with intention to fit spare 2.1 l had. Fitted spare engine and as you know now have compression leak.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 14:33
by maxstu
One mullered pancake

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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 14:35
by maxstu
Inlet heater chamber full of melted carb. Some bits found their way to camshaft?

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Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 14:45
by maxstu
So lve got a budget of £300. Sold my Caravelle captain chairs.
What tools do l need to take measurements to find whether components are within tolerance?
New l have:
Full gasket set
Sealant
Pushrod seals
Sump plug
Piston rings
Oil pump
Oil
Filter
Coolant
Second hand
Inlet manifold
Crank
DF cases.
Time aplenty.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 16:00
by T25Convert
I did mine (build thread here https://club8090.co.uk/forum/viewtopic.php?f=37&t=120790" onclick="window.open(this.href);return false;) using nothing more than a cheap Chinese digital micrometer and some feeler gauges.

The resolution on these is fine, bearing in mind that most of the time you are only looking at relative differences, and hence errors tend to cancel out. If you look at buying top end measuring gear its mostly more expensive than just buying new bits!!

As said above you are looking for a good solid engine, not race spec 100% perfect.

Good luck with it, I really enjoyed doing mine and perversely would quite like to do another at some point....

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 17:34
by maxstu
T25Convert wrote:I did mine (build thread here https://club8090.co.uk/forum/viewtopic.php?f=37&t=120790" onclick="window.open(this.href);return false;) using nothing more than a cheap Chinese digital micrometer and some feeler gauges.

The resolution on these is fine, bearing in mind that most of the time you are only looking at relative differences, and hence errors tend to cancel out. If you look at buying top end measuring gear its mostly more expensive than just buying new bits!!

As said above you are looking for a good solid engine, not race spec 100% perfect.

Good luck with it, I really enjoyed doing mine and perversely would quite like to do another at some point....

Thanks very much T25Convert.

Have put together comprehensive measuring kit.

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By the way, l read your posting about two weeks ago. Thats where l first read about using a wobble extension bar to remove conrods from crank. Dead easy. Then l can remoce gudgeon pins at a leisurely pace...and position. :ok

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 17:47
by maxstu
Has anyone removed the ring wheel from camshaft and bolted on a replacement? Speaking with club 8090 Steve near Gravesend, he suggested this option.
Grind off rivets replacement ring wheel and use high tensile bolts.

Re: Virgin DG1900 Stripdown With Photos. Oooer!

Posted: 15 Feb 2019, 17:55
by itchyfeet
maxstu wrote:Has anyone removed the ring wheel from camshaft and bolted on a replacement? Speaking with club 8090 Steve near Gravesend, he suggested this option.
Grind off rivets replacement ring wheel and use high tensile bolts.


yes, although I never fitted either

bolting it with M7 bolts

https://club8090.co.uk/forum/viewtopic.p ... 5#p8142886" onclick="window.open(this.href);return false;

riveting it .

https://club8090.co.uk/forum/viewtopic.p ... 0#p8158748" onclick="window.open(this.href);return false;