Perkins 4-108 starting in cold vs warm state

[skipperpete]

Well you’ve got me there Searles, never in my entire career have I seen a diesel with 27:1 comp ratio, that engine must have been hard to spin over cold and dead, not saying they don’t go that high.... just that I haven’t met one yet. I think my Gardner had more than 13:1, it had a crank handle that took out my top lip when it couldn’t get over TDC.... ever tried drinking beer through a straw. I have a generator with a single cylinder aircooled Yanmar... pull cord start ...and I reckon that’s up in the 20’s, very hard to pull over.
I went through a series of experiments over the years with various cold starting shortcuts, ether was popular but damaging( and still is popular in subzero conditions), petrol soaked rag, any aerosol including non water based flyspray, WD40 , LPG burner straight into the air intake but the only one that stood out was the hair dryer type paint strip gun. It didn’t use up all the oxygen like the flamers, safer by a long shot than ether and petrol and it just worked

[alistair]

I have just replaced my old M92 Perkins with a brand new M92b, more or less the same engine. The old one was running great, but had high hours and as I was planning a 16 month Atlantic circuit, I went for the new engine. What you are describing is almost certainly a minor air leak in your fuel line and not a fuel pump problem. It could be the lift pump, the filters or indeed a fuel pipe. The fact that it will run fine after the initial start-up suggests that somewhere air gets in and the fuel in the line runs back to the tank. You could prove this by setting up a temporary gravity only tank, missing out your entire boat fuel supply line and see how it performs. Good luck