Ignition has me stumped

no I got that :).

mine was heavy through oil cap even though rings. Tbh valves wouldn't make it breathe only affect compression as would go out the exhaust. Only if the stems were massively worn too. Top and bottom of engine are linked for oil to drain out
 
On my newly ringed engine I got about 150psi(10bar ish) across all cylinders immediately after the engine went back together. I agree. if oil down the bores doesn't make any difference then if there is a problem(discounting the gauge) then it must be valves, and the heavy breathing could be down to worn valve guides.
But if the rings are worn then yes you would get heavy breathing at the top end coming up past the cam and push rods. Another thing to check is if the crankcase breather is clear.
You went on a trip in the Highwayman a little while ago I seem to remember, was it OK then
 
...mine was breathing a fair bit at 115-120 but it was running ok at that...breathing worse later on but never measured compression then..thats alloy HC though as I think is Pankys
 
No not had the Highwayman on the road as yet. Only been shunted around the yard. And it's been fairly good up til the last few times I've run it - starts fine then quickly gets lumpy then looses all power, sputters, bak fires then it eventually sputters out. 10 mins later starts fine again, but once heated up repeats as above. This has gotten worse and worse. And today the breathing was so bad the van was full of smoke :p

I think I need to do some good going over of the engine. I have already done the ignition, new fuel lines and pump. New diaphragms in the carbs. Sorted a sticky float valve. I think I need to get to the bottom of the compression with a good tester before i delve much further. But new inlet gaskets and carb service is a must also.

Tom
 
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Luvley morning to be working on the van :)

Picked up a (new) compression tester today. And showing 150psi within 5 psi across all cylinders!! Cheap ebay tools grrrrr.

SO...

Taken the air filter off which is rather gummed up. Gave carbs a quick blast through with carb cleaner, it's had new diaphragms already. Sliders seemed a little sticky. Cleaned plugs, reassembled and she ran sweat as a nut for about 1 min then started spluttering and konked out.

Got to be fuel issue. Made me think, one of the carbs was flooding fuel on me a few months back and I cleaned out the bowl presuming a float valve issue. Sorted that problem. But bet the other carb is gunked up too, follows that I'm getting about a chambers worth of fuel out of both carbs then the one carbs dropping out of action making it run like a dog.

Assume the breathing was down to the chugging, huffing and puffing when it was running bad. Seems fine for the minute it's running right.

Thoughts??

Tom
 
Great compression!

My thoughts:- If it is snakeskin/crud you have to check/clean all fuel filters and maybe blow back through the tank exit. You may have tiny filters at the carb entrances too.
 
One thought - can't use carb cleaner on diaphragms as it instantly destroys them (if it got in there). I did it on my old carb with a new one in and it shrivelled there and then...that could be the issue?
 
That's great news, the compression is excellent. I think you may have hit the nail on the head with the carbs, even though you've been through most od the system that last little bit has probably come back to bite you in the rear.
 
Well I pulled the carbs on Friday. Did a complete strip, clean and reassemble.

Found a loose bolt on the flange to inlet manifold - pulling air?
A fair quantity of scum and matter behind one float valve, visibly restricting flow.
A bent pivot 'clamp' on one float
A blocked float valve.

Think that was all!

Reassembled and seems much happier. Not surprising really.


Moving her to the workshop tomorrow for the start of the respray!

Tom
 
Hopefully that will sort it. Remember we want to see the finished product please:)
 
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