Wet sumping while running

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
Post Reply
User avatar
Harry44
Member
Posts: 279
Joined: Sat Dec 17, 2016 5:26 pm
Location: SOMERSET UK

Re: Wet sumping while running

Post by Harry44 »

At least I'm not the only one to suffer wet sumping with the engine running. Hope you get yours fixed


Harry
si is does non opportunus vos postulo a maior pango
SPRIDDLER
Member
Posts: 8542
Joined: Wed Sep 01, 2004 1:00 am
Location: WEST SUSSEX UK

Re: Wet sumping while running

Post by SPRIDDLER »

56G80S wrote:Sprid

Thanks. Mine will pass through the bush. Cheeky but where is the data on wear limits?
Where relevant I use the Army Inspection Standards for my '54 model. Good move to check the wear limits as I've no idea why, (probably senility) I gave you the wrong dims for bush wear :oops: although your bush seems to be right on the acceptable limit.

http://archives.jampot.dk/book/Workshop ... ndards.pdf

See page 8........
Bush timing side dims (640x321).jpg
You do not have the required permissions to view the files attached to this post.
'There is a tide in the affairs of men
Which taken at the flood............'
56G80S
Member
Posts: 3353
Joined: Wed Oct 12, 2005 10:45 pm
Location: N YORKS UK

Re: Wet sumping while running

Post by 56G80S »

Thanks Sprid

It took me a while to work out but I realise that 6 thou looks like the condemn point. I was only guessing at the play. Short of a dial gauge on the end of the axle..............

I reckon the play is too great and it's stuffed one way or another but perhaps not so much that the pump plunger will be as well (hopes).

I'll pick this up again when I get the cases split.

Cheers

Johnny B
56G80S
Member
Posts: 3353
Joined: Wed Oct 12, 2005 10:45 pm
Location: N YORKS UK

Re: Wet sumping while running

Post by 56G80S »

Rocker box and head off now. What a lot of carbon. It had obviously been running too rich but at least it's not oily. I probably left it rich for the running in after barrel re-sleeve and didn't weaken it later. Somewhat oddly, both pushrods were very, very slack. Maybe I did this when I was carrying out explorations at the Jampot. I really hope so.

Put some 3-in-1 oil in the top threads of the barrel nuts and maybe I won't wind the studs out like last time I took the barrel off. MIght pop some Plus gas in too. They tend to get water sitting in them.

Johnny B
56G80S
Member
Posts: 3353
Joined: Wed Oct 12, 2005 10:45 pm
Location: N YORKS UK

Re: Wet sumping while running

Post by 56G80S »

Me again

Well, the nuts came off nicely. Unfortunately, the barrel is naughty word, naughty word. the inlet side of the piston is also naughty word. The former is cored sufficiently that I can feel it through the "rubber" gloves. I wonder it T&L can remove the liner and do it again? The piston has at least one piece of brass and probably more tightly ensconced in the line with the inlet valve.

Ironically I had made a nice job of reaming the small end and fitting the piston.

Lost heart at this point and will proceed to removal of the engine tomorrow or over the week-end.

So the target now is Easter next year.

Johnny B
User avatar
Harry44
Member
Posts: 279
Joined: Sat Dec 17, 2016 5:26 pm
Location: SOMERSET UK

Re: Wet sumping while running

Post by Harry44 »

Heart breaking I feel for you mate

Cheers Harry
si is does non opportunus vos postulo a maior pango
56G80S
Member
Posts: 3353
Joined: Wed Oct 12, 2005 10:45 pm
Location: N YORKS UK

Re: Wet sumping while running

Post by 56G80S »

Engine now out of frame as well as the AMC gearbox.

I'll speak with Alpha Bearings w/c 04 January about getting work done as they did the bottom end last time, back in the 1970's.I'm confident that the barrel / piston is too badly damaged to be managed by a rebore and new piston. T&L relined the barrel only a couple of years ago and there were a couple of hiccups. I'm tempted to save carriage and send all to Alpha.

I now find that the drive side axle splines are worn and when the weather picks up I'll post a photo or two for an opinion on what's what. Setting aside the pandemic, when all's back together (but with the Burman box back in as there's some work to do on the AMC) I anticipate covering plenty of miles. I don't want to change things for the sake of it but wold feel a fool to have the pin and timing side done and then find the drive side lets me down. On the other hand, new parts may not be of the same quality as the old parts.

Looking forward to a better 2021 for us all.

Johnny B
User avatar
cfaber
Posts: 346
Joined: Mon Nov 20, 2017 5:37 am
Location: USA, Colorado
Contact:

Re: Wet sumping while running

Post by cfaber »

Well, after a bit of time I've finally moved back onto this project. Here's the measurements I very, very carefully took today on a nice (actual size) pump shuttle.
shuttle (thou).jpg
Plunger limits.jpg
You do not have the required permissions to view the files attached to this post.
Fix it until it's broken!

Otherwise how will
anything get done?
User avatar
cfaber
Posts: 346
Joined: Mon Nov 20, 2017 5:37 am
Location: USA, Colorado
Contact:

Re: Wet sumping while running

Post by cfaber »

So based on the above, at least according to my math (which admittedly isn't great), appears to be within spec. So that said, if the oil pump isn't the issue where else should I be looking to solve my wet sumping problem?
Fix it until it's broken!

Otherwise how will
anything get done?
User avatar
Pharisee
Member
Posts: 1126
Joined: Tue Mar 15, 2016 8:51 pm
Location: Lincolnshire UK
Contact:

Re: Wet sumping while running

Post by Pharisee »

This is a long thread and I admit that I haven't looked back at all the posts but my '55 M18S started to smoke badly and I found that the oil wasn't being returned to the tank. The problem turned out to be the cap on the return end of the oil pump housing. A previous owner had put it on with slotted head screws which meant that I couldn't check them with the engine in the frame as there was no way to get a screwdriver onto them. With the engine out, I found that one was tight, two were loose and one was stripped. Air was being drawn into the pump rather than oil from the crankcase. A Helicoil insert, four correct screws and a new gasket cured the problem.
John
I'm from the Fens.... Gimme six.
Post Reply