Engine not starting when cold

[lawrence_craig]

Hi guys,

My Volvo Penta D2-55D won’t start unless I put some revs on it after being at anchor at night.

If I start in neutral, it will start but then immediately stop. It’s not a battery issue.

It will only start if there are revs on. I changed the fuel filters so I’m considering possible issues with head gasket and compression. What’s your thoughts? I did have an over heating issue a couple of times that’s now resolved. Again hence my thoughts on head gasket.

For a note, if the engine has been running for 2 or so hours, and I stop for lunch, it starts rough and in neutral but doesn’t need revs.

Cheers

[DeepFrz]

Check for air leaks in your fuel system. The fact that it starts and then stops tells me that there is air in the fuel system. Just a hunch.

However you may want to torque the head bolts to spec and check/adjust the valve clearance.

[rbk]

Do you mean additional rpm/throttle by ‘revs’? If so that is fairly normal. A lot of diesel startup procedures call for throttle to be at max or increase for starting. I wouldn’t go straight to head or compression problem. Just sounds like a cold engine. Also how cold (ambient temp)?

[Sailmonkey]

Define cold?

It’s very normal for diesels to require additional throttle to start and stay running when cold.

[Cadence]

From what you have said I would suspect you are sucking air into your fuel line.

[lawrence_craig]

Cold is not having ran for at least 12 hours and at ambient temperature (15-20C).

[lawrence_craig]

Checked fuel line, plenty of diesel in tank and all rubber hoses are fine

[rbk]

have you checked your valve tip clearances lately?

[scherzoja]

It sounds like air getting into your fuel line.

I had a problem that sounds similar. Engine starts (similar environmental conditions as you), runs for minute or two, then stops. Crank and crank and crank, no good. I ran the fuel pump opened the bleeder valve to purge air (Kubota block has a small rotating valve that I open to purge air, really slick), then starts. Sometime stops again, sometimes runs for a while.

Turns out it was an air issue I caused. I removed the generator and filter months before to rebuild and didn't do a good job sealing off the fuel line from tank to generator (FYI: Threading a 5/16" bolt into the end of 5/16" fuel line will not seal it very well!). In addition, the generator fuel input line was T'd off the main engine pickup at the tank. Air was being sucked through the end of the generator line, past the T and into the engine.

I fixed it by removing the T and giving the generator its own pickup tube in the main tank (actually, I designed and made a new tank so each device, gen, engine, heater has its own pickup and return.

I never was able to confirm that it was air because I never saw air bubbles (or was not smart enough to look). All I know is that when I replaced the tank and hoses, I no longer had the issue, except that one time when I didn't tighten a hose clamp enough and air was getting sucked in, causing some run failures. Double check hose connections to make sure they are tight enough.

[Sojourner]

It might be normal for some engines to need throttle, but not all...our 26 year old Perkins starts up on the first half a crank every time in every weather in neutral... More important, I think the OP would know if this was the case through the life of the engine so far, but it sounds like a new problem. Check for air leak.

[roverhi]

Engines that don't have glow plugs or other heat sources for the combustion chamber need to have the throttle open approximately 1/2 way or even more to start from cold. My Yanmar's will start in Hawaii and SoCal's warm temp's with throttle at idle but idle rough on one cylinder for a short while before smoothing out. Giving them a bit of throttle makes starting much smoother. Starting in SF's cooler temperatures took more throttle to get them to fire up on both cylinders.

[rbk]

Originally Posted by Sojourner

It might be normal for some engines to need throttle, but not all...our 26 year old Perkins starts up on the first half a crank every time in every weather in neutral... More important, I think the OP would know if this was the case through the life of the engine so far, but it sounds like a new problem. Check for air leak.

Would love to see this work in January in Alaska All kidding aside when our Perkins is warm-ish it starts at idle but a bit of throttle definitely stops any hesitation and starts instantly. Shoulder seasons when the water temp hovers around 5 centigrade and the engine bay and block are about the same it needs some throttle and smokes a bit until it warms up. If i throw a heater in under the doghouse for the evening it will start at idle with little to no smoke. No glow plugs, no thermo start.

[morribabes]

Check your glow plugs. they may have gone open circuit.

[DameGravey]

I had a similar issue with our D1 30, simply fixed by replacing the glow plug relay.

[waterman46]

Originally Posted by Sojourner

It might be normal for some engines to need throttle, but not all...our 26 year old Perkins starts up on the first half a crank every time in every weather in neutral... More important, I think the OP would know if this was the case through the life of the engine so far, but it sounds like a new problem. Check for air leak.

Ditto, our 36 year old Perkins starts every time almost before I have time to react to the push on the button. Throttle in idle position. And Perkins has no glow plugs. On the other hand, my Onan of the same age requires a 30 second glow plug run and then only starts after at least 5 seconds of cranking. Finally will catch, gradually and it seems with a great protest that I woke it up and will make it do a little work.

Sorry, off topic I guess. Hope OP can find the air leak.