Author Topic: JP2 rebuild  (Read 796 times)

Norm Prior

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JP2 rebuild
« on: October 29, 2017, 06:59:06 PM »
Hello. About to start looking at rebuilding a JP2.
As there are JP3 parts available I wondered if the heads off them can be used without issue.
I've not seen any issues raised previously.
Engine will be used on a proper load - not a hobby engine.
Thanks

AdeV

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Re: JP2 rebuild
« Reply #1 on: October 30, 2017, 08:22:58 AM »
AIUI, everything above the crankshaft should be interchangeable between JP2 to JP4 (was there a JP6?) models - i.e. rod, piston, rings, barrel, head, injectors, cap & nut.

Fuel pumps will be different, the crank obviously, possibly the flywheel is bigger on the JP3 vs. JP4 (I don't know). Oil pump may be the same, again, I don't know for sure.

Which bits are you looking to replace?
Cheers!
Ade.
--------------
1x Lister CS Start-o-Matic (complete, runs)
0x Lister JP4 :( - Sold to go in a canal boat.

listard-jp2

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Re: JP2 rebuild
« Reply #2 on: November 01, 2017, 06:22:38 PM »
hash=item362410733e:g:0j8AAOSwa3BZ7HPQ
AIUI, everything above the crankshaft should be interchangeable between JP2 to JP4

Would that include the camshaft and manifolds  :laugh:

Oil pump may be the same, again, I don't know for sure.

It is, but the oil pickup and gauze strainer will be different.




As there are JP3 parts available I wondered if the heads off them can be used without issue.

The heads are interchangeable, the only caveat being if the JP3 / JP4 cylinder head has/had the integral water pump fitted, like this one that AdeV recently sold on the maiden bid:
https://www.ebay.co.uk/itm/Lister-JP4-engine-complete-and-running/23253329183

Then to use that cylinder head on a thermosiphon JP2 you will have to carry out some modifications on the internal water passages and fit a blanking plate over the hole left by the water pump to make it work as properly.

I have available some new JP (wearing parts) parts, if your interested send me a PM to discuss in more detail.
« Last Edit: November 01, 2017, 06:24:17 PM by listard-jp2 »