Perkins 4-108 starting issue

[David VanDenburgh]

This isn't critical, but I thought I'd solicit some input. Here's the situation:

'79 Perkins 4-108 with about 2000hrs on it. It has always started within a second or two - even after a long winter layup. Just recently it has been taking more cranking to get her to catch, on the order of about 5-8 seconds. It's really not that long, but certainly longer than it used to be. Once it fires, it runs fine. No hesitation. No "hunting". No power loss. No smoke.

Since we just hauled, I haven't done any troubleshooting. The fuel filters were changed perhaps 50 hrs ago. The air filter is clear. Battery is in good shape.

Is this a non-issue, or perhaps the beginning of something? Here's a link to a video of normal engine starting during spring commissioning.

I appreciate your sage advice.

[Ceasar Choppy]

I know my 4-108 gets a little stubborn when it starts to get a little chilly outside. I don't have a fuel pre-heater or glowplugs. It usually works OK if I open up the throttle a bit more and crank a second or two longer now that them temp at night is below 50 F. The only other thing I would say is that unless your filters are BRAND NEW, you can't rule out the possibility of them being dirty and affecting your starting. But my money is on ambient temp.

[David VanDenburgh]

. . . my money is on ambient temp.

That was my suspicion as well, especially since we don't have a pre-heater. I will swap out the fuel filters in the spring as part of commissioning, but I'd be surprised if they're to blame.

Thanks for the feedback.

[boatsnh]

I've got a westerbeke 4-107 in our dickerson. We just hauled a couple weeks ago in Portsmouth NH. Last couple of starts were a bit hard - temp in the high 30's overnight & mid 40's on the boat 'till about 10:30 am. A bit of "verbal coaxing" and extra throttle did the trick. I changed both fuel filters 15 hrs ago, so I know it was not fuel - brought a propane torch to "pre-heat" just in case she did not want to fire the morning we hauled - a few "extra" seconds vranking & fired right up. Did not need the torch. Guess I'll have to get the fuel pre-heater system up and running for next year. but I said that last year too....and the year before that.....
Mike

[megalops]

Yours starts a little quicker in that video than my 4-236s do. Is the engine cranking slower than usual? It could be a weaking starter or possibly some corrosion on the starter cables which is causing a little voltage drop.

Also, on my 4-236 there is a small filter screen on the lift pump. Since this is in front of the engine mounted fuel filter it could be a little clogged even if the filter is clean.

[ddsailor25]

Agree that it's most likely the temp, but you could also consider the age of the fuel. If you do need a little bit of a kicker on really cold starts, use wd40 in the air intake. It's not as explosive and will fire a diesel up safely.