Perkins Starter / Solenoid Problem

[gruffa]

We have a Perkins 4-108.
When we hit the start button we get a single click each time.
Have checked cable connections and battery charge, ok.

have tested wiring direct from ignition (white wire) terminal to start switch, ans starter motor whirs ( which doesn't make sense to me. I thought it would just click)
Same if i take that wire direct to battery.
If i short the large positive lead on the solenoid to the ignition terminal, the starter whirs.
If i short the large positive lead to the ground terminal, the starter whirs.

My only thoughts are that the solenoid is not engaging it's lever to push the starter motor gear into mesh with the flywheel.

Can't figure why the wire from start switch to ignition terminal makes the starter motor whir. I thought it would be only trying to activate the solenoid, which wouldn't contact and make the starter motor start go until it has pushed the gear forward.

??
any ideas?

james

[ColdFusion]

Have you tried shorting the start button cables where they terminate at the start button? If the starter operates it's a faulty start button.

[Bloodhound]

I think the solenoid has two functions: (1) it directs power to the starter motor (making it whir) and (2) it activates the electromagnet that engages the starter motor gear with the flywheel. Step 2 is obviously not happening. The question is, where's the electromagnet? Is it part of the solenoid or god forbid, part of the starter motor assembly? Wish I knew, but a check of Caldwell will probably reveal all. As Coldfusion writes, is it activated by a separate circuit routed through the starter switch. I've replaced switch and solenoid on my 4-108 and it turned out to be a starter switch problem (too much exposure to the elenments) when the starter didn't even click (on returning to marina), but jumping across the solenoid worked.

[btrayfors]

Had same sort of problem with my 4-108 beginning some 12 years ago. I think it's in the harness assembly...resistance somewhere, bad connectors, bad switch contacts, etc.

Remedy: I installed a marine pushbutton switch in the engine room, wired directly to the solenoid. This allows me to start the engine from the engine room (I did it just today). It has NEVER failed. Starter motor spins up powerfully, and engine starts with just a revolution or two.

Often, I leave the ignition key (in the cockpit) in the ON position. When the motor stops, I just turn off the battery switch located near the engine room. This way, I can start and stop the engine from down below if necessary.

Yeah, I know I should replace the entire harness (and probably the instrument panel, too). Seen a lot of salt water miles and a lot of salt water splashing about in the cockpit and on the face of the panel. No doubt connections behind the panel are corroded. But, it's virtually unreachable and a major job to do (some helpful soul installed it with 5200). One day..... :-)

Bill

[Chief Engineer]

I have seen a number of long range cruisers set up with a start button in the engine comaprtment....Or you could by a remote starter swich with alligator clips.

It helps if you are blleding injectors single handed.

[gruffa]

thanks for your rapid replies.

i had success this morning after laying awake many hours thinking it through.

First i checked all the wiring and tested for voltage drops/leaks. All seemed ok, but i'm no expert on electronics. ( Have Nigel Calder's book , and it helps a lot)

Then i reasoned...we can get the solenoid to click, and the starter to whir, but seperately. Why not try both at the same time?

So I had my girlfriend hold the satrt button while i cabled directly from the ignition terminal to the battery. Starter whirred, then grinded a little. Stop.
Then i just tried the cable direct to the battery again from ignition post and the engine turned over and started. Great reflief.

I'm thinking, maybe the solenoid still isn't properly engaging the lever to the starter motor, but it is just enough.

So i might need an engine room switch by the sounds of it.

James

[gruffa]

I'm still getting grinding noises trying to start my engine this way.
Might have to take the starter off.
Has anyone had trouble getting to their starter motor like on my Cal 39?
I think i have to take off the exhaust manifold and cooler pipes to get at it.

james

[Bloodhound]

A grinding noise to me would indicate the small gear on the starter motor is not being thrown far enough to engage fully with the flywheel. If the starter motor was able to start the engine you probably don't need to look any further than the solenoid. But if you're bypassing the solenoid and going directly to the starter, the gear on the starter motor may be sticking or the electromagnet weakened or receiving too low a voltage - in either case, I don't see any choice but to remove the starter motor. And replace the solenoid at the same time. On my boat even changing the solenoid is an agonizing task requiring one to suffer through the slow removal of skin from various places on ones working arm. Removing the starter is even worse and cannot be done without removing a manifold or two. These things are misnamed engine rooms --- they're engine compartments of the smallest possible dimensions, just enough to see what needs doing, but not enough room actually to do it without physical pain.

[S/V_Surya]

I just finished doing battle with my starter on my perkins 4-108. I have removed it so many times I can do it in 5 minutes now. Took to shop and had it tested (5 dollars). Turns out it was failed power lead from battery. Voltage was good but could not deliver amps. Got a click when it engaged but could not crank. Took me 2 months to get it it figured out.

[forsailbyowner]

I went through same thing. I took the starter to a shop and had it serviced, it worked for a year. The next time it failed I bought an aftermarket starter with gear reduction. It spins a little slower but still starts promptly. The motor is smaller diameter which makes that pesky inside bolt much easier to get at with a socket and 12" extension. Before I had to use a cut off box end that turned about an eighth of a turn at a time and usually ended getting fished out of the bilge. That darned solenoid was a headache for a long time. When it started acting up it would do just as you described, spin and not engage. Often after a few tries it would engage and start. Cleaning corrosion out helped a few times. It didn't work though the time I finally replaced it. New aftermarket was about $200

[John A]

I had a similar problem with my Perkins and had to finally resort to having a mechanic look at it. After checking everything he darkened the engine compartment by covering himself and the engine with a blanket while I turned the ignition key. There was arcing from a crack in the copper strap that attaches the solenold terminal to the starter.
The solenold's function is to pull a electro magnet as a switch to connect a larger voltage circuit to engage the starter motor which in turn spins a Bendix gear which then engages a gear on its shaft to the flywheel. The 'click' is caused by the movment of the electro magnet within the solenold.

Solenolds are also used between a propane tank and the regulator, and on electric anchor windlesses.
I hope the problem has been resolved
John

[glhotka]

I was originally going to rebuild mine, but in the end found that an aftermarket one new (no core charge) was about $130-150. I figured at that price, I would replace it new and in the end I am glad I did. I will still likely have the other rebuilt or rebuild it myself as a spare. Heck Amazon even has them now with free shipping so you don't have to taxi all over for the darn part

We ended up writing a couple of blog posts and also doing a 2 part video on our youtube channel on how to replace it, with close up videos, troubleshooting as well as adding a remote start button in the engine room.

Hopefully you find it useful.
Here is a link to the video on our Youtube Channel - https://www.youtube.com/playlist?list=PLlwpbgibX_O-K0qoJFcCVlxK8ETIBXgG_

Part 1 - Blog Post - Removing and troubleshooting
Part 2 - Blog Post - Replacing and remote start