Oil pressure on Winsun 188FB

[Michael Gilbert]

Hi All, I am finishing off a 1979 Enfield diesel using an engine and frame mods etc from Price Parts. I thought it would be a good idea to fit a oil pressure gauge. When I start the engine, at anything above tickover the gauge goes straight to max (100 psi) I've tried three different gauges and the same happens. Has anyone else fitted a gauge to a Winsun, or any other Yanmar clone engine ? What was the result ?. I hope to bring it to the Big Knock in may. Michael.

[pietenpol2002]

Welcome to the forum Michael.

Yanmars and their clones don't have a pressure relief valve. Thus, pressure spikes at cold start-up and diminishes with warm-up. By all accounts, nothing to worry about. Unless of course you plan to hang a tubo, where you could run the risk of pushing oil past the turbo seals. At which point things would get real exciting.

https://www.youtube.com/watch?v=u_kE93kV7Sw

[Diesel Dave]

My Yanmar clone is the same, nowt to worry about unless you are considering adding external oil lines, (I’ve seen an oil cooler explode previously).

If you do blow a turbo oil seal you can end up with a runaway engine, that gets exciting really fast.

Try and use decent multi grade oils, although I tend to use ASDA semi-synth as you get a full 5 litres in a bottle.

[Diesel Dave]

BTW shout if you need a hand as I’m not that far away.

If you can fit a Cush drive clutch then your transmission and final drive chain will last a lot longer.

Make sure your primary chain runs as true as possible, easy to do with a camlock bush primary sprocket.

It’s always worthwhile rebuilding the gearbox when you fit the new mainshaft, or at least check the bushings for wear and relieve the sprocket shaft so it’s a push fit into the big bearing rather than needing a hammer. The quadrant spring loaded indent plunger needs checking as some left the factory without being hardened and will wear away causing it to drop from neutral into first on its own accord.

There are lots of tweaks to the rolling chassis too, especially if your using the twin leading front brake and remember the rear brake is supposed to have a floating pivot so it centralises.

[Michael Gilbert]

Thanks for the replies, its reassuring to know there's nothing wrong with ski-high oil pressure. I've got the bike on the road, mot'd etc. At first I found it to be undergeared (18t g/box sprocket as advised). I've partially overcome this by fitting a huge/tall 400x19 rear tyre. I'm happy to just gently ride it around and get some miles on it before seeing what it will do. The speedo I bought from Hitchcocks is grossly inaccurate even with the big rear tyre (79 model speedo driven from r/wheel) so I've sent it back. Hopefully they'll replace it with one that they've "checked for accuracy" I've overcome the crap single sided front brake by fitting a rear brake arm and converting it to cable, same spline, more leverage. The MOT chap put it on the rolling road and said the brakes were good. The one thing that I didn't account for is the racket (knock) that the engine makes when its under any kind of load, I assume as its new, its correctly set up and myself, the neighbours and the surrounding area are just going to have to get used to it. I'm counting the days till the big knock rally in the hope that there will be other Winsun engined bikes there for me to compare with. See you there. Michael.

[Diesel Dave]

Every Indian speedo I’ve ever had has been close to hopeless, fit a bicycle speedo for accuracy.

If it’s knocking very hard then it may be worthwhile retarding the timing a little, (extra thin shim under the pump). The pump diesel in the U.K. is quite a high cetaine rating so ignites quickly advancing the timing compared the usual crap used globally.

Might be worth waiting till after the BK when you can compare with other bikes.

See you there.

[Michael Gilbert]

Dave, "A bicycle speedo" ? Are they some sort of electronic gadget these days. I will investigate this further. If its a little digital thing, that could be just what I'm looking for.

[Diesel Dave]

Cheap as chips, don’t try a wireless one...



When you calibrate, measure the bike rolling the front wheel wiith you seated on it for 10 revolutions and divide the result by 10 to get the wheel size correct.

[Michael Gilbert]

Dave, Went to Halfords (bike shop) and bought a 9 function cycle computer which the guy said should do the job. I haven't tried to get my head around it yet. It is wireless so I should have checked back on here first. nevermind. More importantly I went out on the bike today and am getting increasingly concerned about the volume of the knock. I figure it wouldn't be a big job to remove the injector pump and install extra shims one at a time and see if things improve. I've seen a guy doing it on Utube but I think he was in the states. Do you know where to get Winsun shims ? A company called L&S do Yanmar ones, do you know if they're the same. Michael.