Rebuilding Perkins 4108

[SailnParadise]

I am preparing to rebuild my Perkins 4108 myself without fully removing it from my boat. I have an Irwin 37. Not in an area with a yard and need to get it running ASAP. A little about the issues I am having: Decent sized oil leak. Left for a month after filling it up and it was almost empty. Stalled twice for what I assumed was the clogged fuel line from a tank full of gunk. Bled lines for days and never got her to turn over. These is a leak at the gasket for the coolant tank to the head. And it was hard to start prior to any of these issues and now it won't start at all. Replaced the Starter, Alternator and fuel pump. Looking for any suggestions to avoid a full rebuild so that I can get it to a yard for haul out.

[Lepke]

You need to deal with the dirty tank and fuel lines first. You need to add a good fuel conditioner that kills any organisms and improves fuel burn. You need at least a triple dose of fuel conditioner. Don't go cheap or you won't fix the fuel problem. I assume you have the stock fuel filter on the engine, but you need a good primary filter like a Racor turbo design that removes water.

You have gunk in the tank because you had water in the fuel. Organisms that eat fuel can live in the tank if they have water. The gunk is their waste. If the gunk got past the fuel filters and into the injector pump, then you have bigger problems.
If you bleed the injector pump and have clean fuel coming out, then bleed the injector tubes. Loosen all the tube nuts on top of the injector. Put some rags around to catch fuel. Crank the engine over until bubble free fuel comes out. The engine shouldn't start with all the nuts loose because there won't be enough pressure to open the injector needle valve. Once you have clear fuel, tighten the nuts an try to start.

If the engine won't start, try some heat, like a hair dryer into the air intake. Or a block heater or pan heater.
How are you losing oil with the engine not running? Either there's a leak in the pan or the pan drain is leaking. Oil doesn't normally leak out of a stopped engine.
If there's a mechanic, get a compression test. Usually hard to start engines have low compression, but that's not the only cause of failure to start.
The leak at the coolant tank has nothing to do with hard starting.
You get water in your diesel either from buying crappy fuel or your fuel tank filler leaks.
If you do get it started, keep several filters on board until the tank problem is cleared out.

[SailnParadise]

Originally Posted by Lepke

You need to deal with the dirty tank and fuel lines first. You need to add a good fuel conditioner that kills any organisms and improves fuel burn. You need at least a triple dose of fuel conditioner. Don't go cheap or you won't fix the fuel problem. I assume you have the stock fuel filter on the engine, but you need a good primary filter like a Racor turbo design that removes water.

You have gunk in the tank because you had water in the fuel. Organisms that eat fuel can live in the tank if they have water. The gunk is their waste. If the gunk got past the fuel filters and into the injector pump, then you have bigger problems.
If you bleed the injector pump and have clean fuel coming out, then bleed the injector tubes. Loosen all the tube nuts on top of the injector. Put some rags around to catch fuel. Crank the engine over until bubble free fuel comes out. The engine shouldn't start with all the nuts loose because there won't be enough pressure to open the injector needle valve. Once you have clear fuel, tighten the nuts an try to start.

If the engine won't start, try some heat, like a hair dryer into the air intake. Or a block heater or pan heater.
How are you losing oil with the engine not running? Either there's a leak in the pan or the pan drain is leaking. Oil doesn't normally leak out of a stopped engine.
If there's a mechanic, get a compression test. Usually hard to start engines have low compression, but that's not the only cause of failure to start.
The leak at the coolant tank has nothing to do with hard starting.
You get water in your diesel either from buying crappy fuel or your fuel tank filler leaks.
If you do get it started, keep several filters on board until the tank problem is cleared out.

I've already cleaned my tank and replaced the fuel lines all the way to the primary filter mounted on the engine. I have also already replaced the Racor and added Dual secondary filters.

The engine stopped twice while transiting the ICW. The first time I replaced secondary filter (only 1 at the time) and ran from a diesel jerry can to eliminate that as a problem temporarily. I then bled and started the engine using a little spray of diesel starter fluid. After 4 hours it died again. No unusual sounds or vibrations. It just died silently. After this I added the second racor and used some injector cleaner and biocide. It seems there is more than 1 issue. Now when I try to start I don't even hear the starter engage.

[SailnParadise]

Just trying to get suggestions before I try to take the engine apart.

[Turtle Blues]

No sound of starter engaging indicates low battery or some electrical issue.
Lepke gave you good instructions that may need to be repeated several times.
Suggest you not undertake disassembly until these external issues are rectified. You say engine stopped quietly, this is a good thing indicating external, probably fuel, not internal issue. Did you verify where the oil is leaking from or to? This is a critical question. I had an oil pressure sensor fail, first leaking then catastrophic rupture. If I had properly identified the source of the leak instead of assuming a gasket leak. it would have been much easier. Just an example of external vs internal issues. Solve the outside issues first.

[skipperpete]

Originally Posted by SailnParadise

Just trying to get suggestions before I try to take the engine apart.

After a year of reading your posts about the ongoing problems with this 4-108…( lost lube oil, won’t start, stalls, hollow sound cranking, no cranking, broken injector hold down clamp, glow plugs or no glowplugs, etc etc) I’ve come to the conclusion that you need professional help. Rebuilding an engine in situ is a bad idea, a reasonably competent pro should be able to get that engine out in 2 hours and off to a place where it can be opened up and worked on comfortably. You have to lift it out anyway because of what’s probably a rusted/perforated oil pan to remedy the oil leak you mentioned.

[SailnParadise]

Originally Posted by skipperpete

After a year of reading your posts about the ongoing problems with this 4-108…( lost lube oil, won’t start, stalls, hollow sound cranking, no cranking, broken injector hold down clamp, glow plugs or no glowplugs, etc etc) I’ve come to the conclusion that you need professional help. Rebuilding an engine in situ is a bad idea, a reasonably competent pro should be able to get that engine out in 2 hours and off to a place where it can be opened up and worked on comfortably. You have to lift it out anyway because of what’s probably a rusted/perforated oil pan to remedy the oil leak you mentioned.

That's what I am trying to avoid. I've been slowly fixing the issues. No glow pugs hooked up, fixed the injector clamp (bolt was switched by previous owner so it was too long causing it to be over tightened before it was seated correctly), the starting problems where at least temporarily a fuel purity issue. I will be sailing more than motoring in the short term in order to get her back to the US near a good mechanic. So I just need to get it running well enough to get close to a professional.

Right now my main issue seems to be the Ignition Switch/Alternator wiring. Just bought a new Starter and Alternator prior to the trip where the stall happened. The only other time the engine stalled in the previous months was when the main fuel line came out of its ziptie and touched the belt which caused air bubbles. So my thought would be the fuel again. I wasn't getting clear fuel at the return after the injectors so I need to solve that problem. I've already cleaned the tank and replaced all lines and filters.

[SailnParadise]

I've come across a wiring issue. On the 8 point buss there are 2 wires that before ran to the ignition switch. #6 Start and #7 IGN. The IGN has no wire coming in. There is no description in the boat book about what feed this connection. Any ideas? #6 goes to the starter (which I replaced with a new cable when I replaced the Starter). Again this is in the engine room. I think this is why I was getting no response when I turn the key.


UPDATE: I hooked the new ignition switch up directly to the starter and got nothing. Is there a way to test the starter without removing it? It's brand new and only used for 3 hours.

[Ixium]

I’ve used a screw driver across the starter posts to jump start it after my ignition wire got something wrong with it.

I eventually wired a push button start downstairs directly to the starter that’ll start it without key or anything.

[SailnParadise]

Originally Posted by Ixium

I’ve used a screw driver across the starter posts to jump start it after my ignition wire got something wrong with it.

I eventually wired a push button start downstairs directly to the starter that’ll start it without key or anything.

Did that a couple of hours ago. Starter turned but wasnt engaging the flywheel. So I just heard a whirring sound of the starter turning. Think it may be shot. Will take it in tomorrow for a look from the shop I bought it from

[skipperpete]

Originally Posted by Ixium

I’ve used a screw driver across the starter posts to jump start it after my ignition wire got something wrong with it.

I eventually wired a push button start downstairs directly to the starter that’ll start it without key or anything.

Yeah that’ll work but unless you have a self exciting alternator you need to have an active positive from the key switch to get the alternator to power up (or from a hobbs oil pressure switch).

[marcjsmith]

The 4108 is a very basic meat and potatoes type of engine. I love mine (all except the rear main seal and the two piece engine mounted fuel filter)

Starter. if the starter is just spinning without shooting the pinion gear to engage. that could be a voltage issue or a broken starter. did you have the proper spacer in place for the starter?

oil leaks. its a British motor its gonna leak oil. if its leaking out while not running then you have a hole in the oil pan or the drain plug is leaking.

the fact that it was running means you've got it it timed well enough and fuel delivery is good. the fact that it runs for 3-4 hours is also good. gotta be more schmutz in the tank or fue lines that is clogging the filters/injectors. an air leak shouldn't manifest it self after several hours.

do you have a good vent on the tank? If not ,possible that as you are pulling fuel from the tank if your tank vent is clogged your tank is creating a vacuum. At some point your lift pump is unable to overcome the vacuum and the engine dies from fuel starvation. Then over the course of a few hours of not running wile you are working on the engine, the vacuum is released. And the engine reluctantly starts.

[SailnParadise]

Starter is working again. Took it in to the shop but I think it was the Starter connection. It was loose. But still having the starting issue. It turns over but sounds hollow. I've bled it every way I know how. When I crack open the nut on the line before the injectors but after the injector pump I get no fuel. But I get fuel from the bleed screws on the injector pump. I'm using an electric pump and pulling from a clean jerry can of diesel. Any suggestions?

[marcjsmith]

TAD made a nice PDF for bleeding with a focus on the 4108...
https://www.tadiesels.com/tech-faq.html

https://www.tadiesels.com/assets/doc...hanging-v4.pdf

not sure I understand the "hollow sound" if you aren't getting fuel through the fuel pump, then maybe you've found your problem.

to get a bit more compression/faster turning I block the air intake crank the motor get it spinning faster, since there isn't any incoming air to compress and then remove the intake block.

[SailnParadise]

Originally Posted by marcjsmith

TAD made a nice PDF for bleeding with a focus on the 4108...
https://www.tadiesels.com/tech-faq.html

https://www.tadiesels.com/assets/doc...hanging-v4.pdf

not sure I understand the "hollow sound" if you aren't getting fuel through the fuel pump, then maybe you've found your problem.

to get a bit more compression/faster turning I block the air intake crank the motor get it spinning faster, since there isn't any incoming air to compress and then remove the intake block.

I'm getting fuel thru the fuel pump. The rate of turn is not an issue. My ONLY issue now is I am not getting return fuel. Fuel flows freely thru the filter and injector pump. I've bled it 20-30 times before this and am very familiar with the process.