Decompression lever will not stay open

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clonberneclassics
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Decompression lever will not stay open

Post by clonberneclassics »

I have just taken delivery of my Royal Enfield 500 cc Diesel bike .Its fitted with a Greaves GL400 engine and i cant start it .The decompression lever will not stay open so i cant start it .Please can anyone tell me how to fix that or tell me whats causing it .I have contacted the company in India i dont think that they understand what i am trying to tell them .It did start once but i think that it was just good luck . I have turned the engine very slowly and tried to find the correct position but it just will not stay open .I have been at this for 4 days now and am about to burn the bike haha .
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Re: Decompression lever will not stay open

Post by coachgeo »

Not sure how it works on the Grieves... my apologies. On the few different diesels I've used where there was a decompression lever... it was made to spring close. You had to hold it open then release the pull cable when you felt the RPM's were up high enough to deactivate.

on my old Yamaha XT550 petrol, it's decompressor was built into a pattern within the kick start..... a complete PITA. You have to be a psychic yogi to know if you've activated it and it get it to release at the right time.
gilburton
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Re: Decompression lever will not stay open

Post by gilburton »

First one uses the decompressor but the other 2 seem to be started without and in flip flops lol
https://www.youtube.com/watch?v=3I7ZQWA6UF8

https://www.youtube.com/watch?v=kC5Xv826Vpg

https://www.youtube.com/watch?v=UKq3Ztsf9uA
bf109v7
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Re: Decompression lever will not stay open

Post by bf109v7 »

Mine stays open only in the position when the exaust valve is closed. Did you try to turn the engine to the point where the compression stroke starts?
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clonberneclassics
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Re: Decompression lever will not stay open

Post by clonberneclassics »

I have tried to open the decompression valve in all positions and it just closes under the pressure of the spring .Its supposed to stay open until just before compression then close automatically .So i cant tell where the engine is in rotation .I have spent 4 days trying to start it :( :(
gilburton
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Re: Decompression lever will not stay open

Post by gilburton »

Sorry can't really help as mine was electric start.
I presume you are familiar with starting large singles of the British variety?
Basically you have to just get it over compression and then give it a big positive swing on the kickstart so that the flywheel will then take it over compression.
Can you describe what you are doing?
Are you getting it over compression or is it just locking up?
If you are getting it over compression but it is still not firing have you bled the fuel line up to the injector??
I only ask as the ones in the videos don't seem that hard to start.
All the decompressor does is hold the exhaust valve open until just before TDC so maybe if you take the cover off and check that the mechanism isn't defective in some way?
Not many greaves engined bikes in the UK as most use the chinese Yanmar clones so info is a bit sparse but I'm sure someone can help eventually.
F2 motorcycles used to bring them in so might be worth an email to them?

http://www.realclassic.co.uk/diesel05112800.html

Taken from another post re starting a Greaves
As for starting, the easy way is this:
1) push the kickstart until it will go no further (engine compression)
2) raise the decompressor lever on the top of the engine
3) push the kickstart very slowly until the decompression lever drops down then stop as soon as it does! (if you go too far repeat from step 1)
4) lastly, kick the starter with as much strength as you can, do not stop towards the bottom, dont worry, you will not break it but your kick should be so hard like you are trying to break it!
If your decompressor is still not working try getting a socket on the crank somewhere and ease it over compression as described(it will turn over compression slowly with a socket) until it eases then kick as described.
It may be your decompressor has jammed or something and it may free off after starting??
Going by the description it only works on compression and releases straight after so only operates in a narrow window?
Hope this helps. Oh and wear heavy boots unlike some of the videos I have seen lol
gilburton
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Re: Decompression lever will not stay open

Post by gilburton »

Any luck??
clonberneclassics
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Re: Decompression lever will not stay open

Post by clonberneclassics »

Hi I have had it running but there still seams to be a problem with the decompression lever .I have tried to get in touch with Greaves but cant find any way to contact them .I will just keep at it .Does anyone know where i can get a manual for the bike .The supplier in Indai wont answer any emails .Its seams that once they have your cash that's it there done with you .Please can you warn anyone thinking of buying from India via Ebay DONT :x :x .I purchased 4 bikes from them and all have issues .Please let you friends know no to trust them.I used my pension payout to pay for the bikes like a fool .Never mind put it down to experience .The feedback that this crowd have on Ebay is very good .I don't know how .
Let me take this opertunity to thank everyone that has tried to help .I will keep you up to date .Thanks
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Re: Decompression lever will not stay open

Post by gilburton »

touchwoodsden
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Re: Decompression lever will not stay open

Post by touchwoodsden »

Did you get this sorted? I have seen these bikes on Ebay and have been sorely tempted.
Merc Estate
BRA CX 3
2 CV Dolly
2 x 250 MZs
1 x 125 4 stroke MZ
2 x 301 MZ
1 x Enfield Himalayan
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Re: Decompression lever will not stay open

Post by Diesel Dave »

The Greaves decomp I'd quite simple, firstly it has it's own tappet to set at1mm it this doesn't make it work then the operating arm is worn down and needs replacing.
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Re: Decompression lever will not stay open

Post by Nathan »

Hi there, I am new tot this forum. Got myself an Enfield 325 Diesel. And cannot get it started too. Same problem I think: the decompression lever will not stay open. Also when using the lever to put the engine just over compression, and kicking it real hard, it will not start.

Did you solve the problem with your bike ?

Any other advise is also welcome.

Thanks,
Nathan
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Re: Decompression lever will not stay open

Post by Diesel Dave »

It's all in the technique - have you tried bounce starting as it's a lot easier?

Firstly turn the motor over until you hear the injector 'gronk' then try this:

https://www.youtube.com/watch?v=j_U-JltnGig
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Re: Decompression lever will not stay open

Post by Nathan »

I got the bike running. after checking everything on the engine a dozen of times I noticed that when kickstarting it might feel like a slightly slipping clutch at the moment of compression. So opened up the primary chaincase, and yes, at compression, the clutch started slipping.
This afternoon I put new plates is, gave it a few kicks and it ran!
pietenpol2002
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Re: Decompression lever will not stay open

Post by pietenpol2002 »

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Congrats on your successful start. Always interesting how solutions are found. And how simple they are sometimes. Now here's to some enjoyable rides. And don't hesitate to share some pics. Or even a vid.
Ron
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