Tricks on starting an old Perkins when cold

[Seamaster_IRL]

Having good battery is a MUST as well as good cables and connection to starter. Don't ignore this as I have seen too often engines failing to fire due to the basics. If a glow plug is possible, suggest you replace and get it working or use hot air as advised in previous posts. I would avoid start sprays as they can easily lead to engine damage. Follow process in Perkins manual to bleed fuel system right up to the injectors (might be a blockage)

Summary
Good battery, cables and clean connections
Check fuel supply at injectors is good
Heat to air intake definitely helps in cold weather
Compression test may help indicate problem cylinders
If all this fails, ya might wanna look at injectors, fuel pump setting etc..

[River Cruiser]

I've used WD40 in place of ether when the glow plug relay went bad on my 3 cylinder mitsubishi on my Westerbeke generator. The main thing is the starter circuit is in proper condition so that the starter spins the engine fast enough to start. The things to check are battery voltage and capacity, a load tester helps here, all connections are clean and tight and the starter isn't dragging. Good luck


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[Cadence]

Avoid ether if at all possible. If you do use it run the engine long enough the oil is restored inside the cylinder. You might try WD 40 I have heard it works spayed into the intake. I have never tried it or are convinced it wouldn't strip lub. oil.

[Lancerbye]

Which model are you talking about? I have 2 4-236s which start as soon as I start to crank them. Some years back one became hard starting caused by a starter that wasn't up to snuff. Rebuilt it and has been good since. Starter speed is very important.

[Zach]

How old are your battery cables?

A lot of hard starting can be corrosion and bad grounds. If you have a battery switch, ohm out the poles and make sure you aren't having voltage drop.

With a diesel you have to spin them fast enough that the dynamic compression stays high. Turn one over slow, and the time between the valves shutting reduces the effective compression ratio... At least until a little oil gets splashed up on the cylinder walls and the rings get wet and start to seal, wet.

Personally I like to see an 8D or better yet a pair of 4D's as the starting battery, and 2-3 foot runs of 1/0 cable. Run the ground to the bellhousing beside the starter, and wire brush the bolts until they are bright.

Install a remote starter solenoid (like they put on ford's...) that has battery power jumped to it from the hot pole of the starter so the starter solenoid on the starter gets full battery voltage, and not voltage through the switch.

When they crank over, it helps a lot of they come up to speed and sound like it's already idling...

Also double check your valve clearance. If they have worn tight when cold, it's a little harder to start than if they fully close.

Zach

[FlyingCloud1937]

As mentioned stay away from either!

Cold oil is the problem with a cold Perkins, that starts easy in warm weather, also cold cylinder walls and rings. As well cold fuel will hamper the fuel pressure to the IP.

A cold battery will have a huge voltage drop, so you won't get the same cold cranking amps to the stater. As mentioned, this will magnify any high resistance cable connections in the starter circuit. All this will eventually lead to a burned up starter.

A magnetic pan heater is out because the Perkins have aluminum oil pans. A KIM Hot Start heater is available for all Perkins, it goes in place of one of the block freeze plugs. It requires AC power, also as mentioned an engine room heater works well if you can have it on 12 hrs before intended start up, but it also requires AC.

A properly working Perkins theromo-start, will be a real aid to starting a cold Perkins if the starter/battery circuit is in working order.

If you have no AC, and or cold start aid. Then cranking on the starter for 20 seconds twice, with 1 minute rest in between before trying to start will help. Make sure the stop solenoid is not in the run position. Never on a CAV pump simply close off the fuel valve. As this will starve the IP.

A better solution, is remove the air filter, then put a 1/2 thick rubber pad to close of the air intake. This is the equivalence to a compression release, which a Perkins doesn't have. By blocking the air intake, there will be no air to compress in the cylinders. This will allow the starter to spin the engine about 2-3 times faster, with almost no load on the starter or the battery. Make sure the stop solenoid is not in the run position.

Also with all Perkins with a CAV fuel IP, the proper way to start is move the throttle to wide open position. This is a CAV design, and is stated in both the Pernins and the CAV manuals. If your engine has sat for a period of time, before cranking put the throttle in the wide open position, and the stop solenoid in the run position, now pump the fuel pump bleed pump about 10 times. This will equalize the CAV inlet fuel pressure. If it's cold, do the above procedures prior to using this method to start the engine, as it will move some oil to stop a dry start.

Lloyd

[NSboatman]

Lived with many Perkins... I love em. you've heard many good suggestions here; and I can't argue with any of em. The thermostart replacement (or glow plugs if you can get em) is the proper fix for reliability; but there are other tricks.

Agreed on the ether - it's not a good idea. That said, I have used it as a very last resort, and then extremely sparingly - sprayed on a rag and the rag held near the air intake only. It worked. i carry a can on board, just because if that's all you've got left, then it might just get you or someone else out of a jam.

I have started many engines using WD 40. It works. heck, you can start a diesel on a nice fog of WD with essentially no fuel coming from the HP pump at all - and keep it running by modulating the feed thru the air intake. Done it several times on Perkins and non-perkins. I wouldn't run an engine for long like this (you need diesel running thru the engine to lubricate things); but it sure can help to start a difficult engine.

A nice trick (slightly risky, so be careful) that has saved my a$$ a couple of times when the batts were nearly dead and the engine was cold was to manually decompress the engine while cranking. This allows it to spin with much less resistance (you're drawing a vacuum on the intake side) and can double the cranking speed in less than 1 revolution. It has literally saved my butt several times.

All you do is pull off the air intake cover, cup your hand over it and make a seal with your palm on the air intake. Hit the starter and you'll feel it try to suck your hand into the air intake. It can't do that though... so don't freak out. As I said, It's a little dangerous, but with the smaller engines it isn't too bad - more of a perception of danger than anything. I don't think I'd do it on a turbo'd engine, but I've done it on 4-108, 4-154, 4-236 and 6-354 perkins models. Also worked on a couple of yanmars and kubotas and even on a farmall tractor.

One thing - DON'T do this if there is a flamestart!!! the flamestarts are in the intake manifolds, and literally light a fire in there... if your hand is the new cap, it will get burned.

Try it - you'll be amazed at how much faster the engine spins when decompressed. Note that it won't actually fire until you remove your hand again and give it a blast of air. This, combined with a nice fog of WD, has started 99% of the recalcitrant engines I've been called on to sort out in cold weather...

YMMV...

good luck!

[Cadence]

Originally Posted by NSboatman

Lived with many Perkins... I love em. you've heard many good suggestions here; and I can't argue with any of em. The thermostart replacement (or glow plugs if you can get em) is the proper fix for reliability; but there are other tricks.

Agreed on the ether - it's not a good idea. That said, I have used it as a very last resort, and then extremely sparingly - sprayed on a rag and the rag held near the air intake only. It worked. i carry a can on board, just because if that's all you've got left, then it might just get you or someone else out of a jam.

I have started many engines using WD 40. It works. heck, you can start a diesel on a nice fog of WD with essentially no fuel coming from the HP pump at all - and keep it running by modulating the feed thru the air intake. Done it several times on Perkins and non-perkins. I wouldn't run an engine for long like this (you need diesel running thru the engine to lubricate things); but it sure can help to start a difficult engine.

A nice trick (slightly risky, so be careful) that has saved my a$$ a couple of times when the batts were nearly dead and the engine was cold was to manually decompress the engine while cranking. This allows it to spin with much less resistance (you're drawing a vacuum on the intake side) and can double the cranking speed in less than 1 revolution. It has literally saved my butt several times.

All you do is pull off the air intake cover, cup your hand over it and make a seal with your palm on the air intake. Hit the starter and you'll feel it try to suck your hand into the air intake. It can't do that though... so don't freak out. As I said, It's a little dangerous, but with the smaller engines it isn't too bad - more of a perception of danger than anything. I don't think I'd do it on a turbo'd engine, but I've done it on 4-108, 4-154, 4-236 and 6-354 perkins models. Also worked on a couple of yanmars and kubotas and even on a farmall tractor.

One thing - DON'T do this if there is a flamestart!!! the flamestarts are in the intake manifolds, and literally light a fire in there... if your hand is the new cap, it will get burned.

Try it - you'll be amazed at how much faster the engine spins when decompressed. Note that it won't actually fire until you remove your hand again and give it a blast of air. This, combined with a nice fog of WD, has started 99% of the recalcitrant engines I've been called on to sort out in cold weather...

YMMV...

good luck!

And I thought starving the air was only good to stop one shot and running on sump oil.

[NSboatman]

works for that too!!

...frigging 6-71's. I've had to do that on 2 of them in a runaway state. my fault for spending too much time on old fishing boats I guess...

bg

[leftbrainstuff]

Originally Posted by Crabby1

Use gasoline on rag and hold over air intake, this is a lot easier on the diesel engine than ether.

This is a well proven old bushman's trick in Australia.

You just need a little warm air on any diesel with no precombustion chamber.

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[Old Swampy]

Because I need to start at near freezing temperatures at the end of the season, and don't have 110 handy, I carry a propane torch to heat the oil pan from below. The bilge and engine need to be clean (free of oil).

[Cadence]

Originally Posted by NSboatman

works for that too!!

...frigging 6-71's. I've had to do that on 2 of them in a runaway state. my fault for spending too much time on old fishing boats I guess...

bg

I had a John Deere D 350 that I kept a rain gear jacket in the seat, not for the rain but to put over the air intake to shut to old girl down.

I had a pair of 6-71s probably the best marine engine ever made. The in-lines I understand the Vs where junk.

Sorry for the off topic.

[tfrank]

I have a 1962 Perkins 4-108 in my Creekmore 36 which was slow to start. I replaced the started solenoid and it starts right up every time even after a few weeks of not being run.

[svHyLyte]

Google (or Click on) "Perkins Flame Start". The system is rarely needed but does work. One must hold the ignition key in the "Heat" position for 30-45 seconds or more.

[CaptNemoO2]

Originally Posted by Campbellcruiser

And it has no glow plugs. Perkins had a system of a coil that burned a small amount of diesel in the intake...it doesn't work.

*WARNING - THREAD DRIFT

It works really well... At making me crazy!

One day I noticed my engine was smoking excessively even after it warmed up. It seemed like it happened all of the sudden, but I wasn't sure, maybe I just didn't notice. The only work I did recently was fix the engine blower. It was white/bluish smoke, so I checked my antifreeze and it was the right level, so it wasn't water. I checked the oil, and it's level was way to high. It wasn't frothy, there was a lot of fuel in the oil. People started telling me horror stories that it's the rings. I assumed it was the high oil levels creating a high crankcase pressure situation leading to blowby. Maybe the lift pump diaphragm was leaking? Maybe the injection pump timing was off, or the injectors were bad? The boat seemed to run as well as always, just smokey, which decreased as the rpms went up. So maybe the timing. I took the injectors out and got them rebuilt, they were off slightly. Put them back in, still smoking. Now I'm thinking it's worse than I thought. Then one day for some reason I checked the air intake screen. When I looked inside I saw fuel pouring into the manifold. Pulled the wire and tada, no smoke!

The engine compartment blower on my boat never worked in the two years I owened it. So I hooked it back up. It turns out, there was a short in the harness that when the blower was on it turned the cold start assist on as well. All the symptoms made sense at that point. Luckily I only spent $150 to get the four injectors rebuilt, which isn't a wasteful thing to have done anyways.

Moral of the story: if your Perkins is smoking white/bluish smoke, disconnect the cold start assist when trying to diagnose the problem. Knowing that would have saved me lots of frustrating time and 3 oil changes, and some fuel! I didn't do the math, but I wouldn't be surprised if this thing was spitting out a gallon an hour.




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