Compression test results?

Compression test results?

Postby BYY922 » Sun Apr 15, 2018 7:57 pm

I’ve just carried out a compression test on my ‘35 14. 1-5 recorded 130 psi and no.6-135 psi. Whilst they’re nice an consistent, I want to know what the bmep is supposed to be as per the factory spec?
Additionally, the plugs (Accuspark AC9CR) are oiling and sooty even though mixture and timing are correct so I suspect they may be too cold, your comments please as to good heat range/make of plug?
Im getting a big plume of smoke after idling or restarting hot so my guess is valve guides?
BYY922
 
Posts: 9
Joined: Wed Jan 03, 2018 6:25 pm

Re: Compression test results?

Postby GOY189 » Sat Apr 21, 2018 9:57 pm

Can't help with bmep but the pressures achieved seem OK. The valve guides do not have seals on those engines. The Accuspark plugs cross ref to NGK B6PRES. Champion N8 or NGK B5ES usually work well, avoid the projected nose plugs (the P in B6PRES). Hope this helps
Mike
GOY189
 
Posts: 329
Joined: Sun Oct 19, 2008 4:08 pm

Re: Compression test results?

Postby Phil - Nottingham » Sun Apr 22, 2018 6:23 am

I use the B5ES in our 1939 16. BPR6ES is a colder plug
P2/P4/P5/P5B/LR's - EXJ 8**/2**8MY & others
User avatar
Phil - Nottingham
 
Posts: 308
Joined: Thu Oct 09, 2008 9:45 am
Location: Nottingham

Re: Compression test results?

Postby BYY922 » Mon Apr 23, 2018 5:40 pm

Thanks chaps. Any idea if anyone would have a set of guides/ valves and ballpark price?
BYY922
 
Posts: 9
Joined: Wed Jan 03, 2018 6:25 pm

Re: Compression test results?

Postby GOY189 » Sun Apr 29, 2018 9:05 am

Meteor spares who advertise in Freewheel can probably help. Engine reconditioners may be able to knurl the guides to improve the seal, reface valves and recut valve seats that are beyond grinding.

Regards
Mike
GOY189
 
Posts: 329
Joined: Sun Oct 19, 2008 4:08 pm

Re: Compression test results?

Postby BYY922 » Sun Apr 29, 2018 6:03 pm

I was always lead to believe that knurling lead to quicker wear due to the reduced surface area. I’d rather press in new ones, but appreciate the advice.
BYY922
 
Posts: 9
Joined: Wed Jan 03, 2018 6:25 pm


Return to Wilks' cars P1 and P2, thats cars up to 1947

Who is online

Users browsing this forum: No registered users and 0 guests

cron