1995 5.8 Volvo/Penta

mcleaves

Chief Petty Officer
Joined
Sep 15, 2003
Messages
521
Re: 1995 5.8 Volvo/Penta

The ECM (same as the ECU) on these motors probably is not the same as that for a car - the two have very different tunes and the auto versions are designed to operate in closed loop with an 02 sensor.

They may be the same base "computer" - I'd think the tune is going to be very different.
Yes, you aren't going to cannibalize a car 'puter for this.

I'd open the wiring harness and simply figure out where the harness is bad - it's likely something rubbed through...
Hell you could just build a new one.

No comment on "rare" 5.8L parts, but the auto equiv's are available when appropriate.
It's the big ticket marine specific items. Manifolds, water pump, coupler, computer etc that are gonna be a the real problem. The fuel cooler is a known corrosion problem and hard to get. It's all that crap.


M
 

dcg9381

Petty Officer 1st Class
Joined
Aug 26, 2007
Messages
308
Re: 1995 5.8 Volvo/Penta

At $5-$6k, I'd go for it, pending a reasonable inspection via a marine mechanic.

If you're expecting to drop money into it - a lot of money - walk away, buy something else. NADA is worthless with boats... I might use it as a ballpark guide. On my boat, it subtracts ~$1500 for the optional motor ($9k option) - and then adds $2-$3k for to the same boat with the same optional motor that's one year newer... It's way off on boats that are "well used" and boats that are very clean.


IF you want a book value for a boat, check out bucvalu.com - they're based on actual sales and will take into account the motor/drive combo.
 

NeverEnough02

Seaman
Joined
Feb 12, 2008
Messages
62
Re: 1995 5.8 Volvo/Penta

Well the ECM is brand new. The injector harness as faulty wires. That would be a swap from a car according to this volvo mechanic. At this point, its looking like a boat worth a survey. I never said i think its value is that of the NADA guide. I worked for dealers in college and i know how that game works. I do see the concept 18 of the same year going for 15k. That is in mint condition of course. I would be willing to drop about 1500 into the boat to get it tuned up and completley relaible. Maybe have some left over for some toys to go with it. I have been keeping my eye on the market the entire time but nothing else has come up. I sent an email on a CC today but if the reply seems to fit what I am looking for, I will start another thread. Thank for the help so far! Any more feedback on those cracks or the fiberglass work?
 

dcg9381

Petty Officer 1st Class
Joined
Aug 26, 2007
Messages
308
Re: 1995 5.8 Volvo/Penta

Well the ECM is brand new. The injector harness as faulty wires. That would be a swap from a car according to this volvo mechanic.

My guess is that the mechanic knows that the injector(s) aren't being fired and that the ECU is trying to trigger them.

ECUs should never need replacement. Having the ECU replaced once is an indicator of a wiring harness issue. Modern injectors can be either low or high impedance, but a short in the injector harness can kill the injector driver (on the ECU).

I work on import EFI - most EFI system have banked injectors ('cept for diesels) - it would be a bit odd to have a single injector drop unless the wiring damage is very close to the injector. A short would take down the entire bank of injectors.

I'm not sure there is an "injector" harness - the whole gaggle of wires is typically routed together.

A "car" harness isn't going to swap... I'd be very suspicious of any mechanic that tells you it will swap - unless he means that he could hack up a car harness and use it to repair this one.
 

NeverEnough02

Seaman
Joined
Feb 12, 2008
Messages
62
Re: 1995 5.8 Volvo/Penta

My guess is that the mechanic knows that the injector(s) aren't being fired and that the ECU is trying to trigger them.

ECUs should never need replacement. Having the ECU replaced once is an indicator of a wiring harness issue. Modern injectors can be either low or high impedance, but a short in the injector harness can kill the injector driver (on the ECU).

I work on import EFI - most EFI system have banked injectors ('cept for diesels) - it would be a bit odd to have a single injector drop unless the wiring damage is very close to the injector. A short would take down the entire bank of injectors.

I'm not sure there is an "injector" harness - the whole gaggle of wires is typically routed together.

A "car" harness isn't going to swap... I'd be very suspicious of any mechanic that tells you it will swap - unless he means that he could hack up a car harness and use it to repair this one.

HMMM. Sounds odd. So you are saying the ECM might need a replacement if the wire shorts and sends power back to the ECM? Figuring out what wires are bad looks like it could be a lot of work. He told me the 5.0 ford harness is exactly the same as the marine version. It makes sense to me but I havent tried it myself. Diagrams that I have found do not show me enough detail. It would be a nice and easy swap though!
 

dcg9381

Petty Officer 1st Class
Joined
Aug 26, 2007
Messages
308
Re: 1995 5.8 Volvo/Penta

So my caveat is this: I've never worked on that motor outside of the auto world before. The auto harness could be similar and if he really knows that motor, I guess it could be.. The harnesses are usually built around the vehicle engine/combination, which is why I suspect they are not exactly the same.
Bottom line - if you have a good marine mechanic that knows that EFI / motor setup, take his word over mine.


The ECM does contain injector drivers - the circuits that power the injector(s). If shorted it could damage the ECM. I have no idea what the protections are on that ECM and what the harness setup is - too many variables - I'm just telling you that it is possible to scrap the ECM via shorting the right things.

ECMs should never need replacement. Ever. They're designed for extremely low failure rates.

If I was in your shoes, I'd probably sign a sales contract pending some success with the repair - the repair being on your dime.. dunno...
 

NeverEnough02

Seaman
Joined
Feb 12, 2008
Messages
62
Re: 1995 5.8 Volvo/Penta

Well I am currently looking for a person to survey the boat. It is in the Ft Lauderdale area. Anyone know a resonably priced surveyor in the area?
 

mcleaves

Chief Petty Officer
Joined
Sep 15, 2003
Messages
521
Re: 1995 5.8 Volvo/Penta

ECMs should never need replacement. Ever. They're designed for extremely low failure rates.

Actually this one was probably replaced after they raised the boat from the bottom of the marina. Florida=Hurricane. Beware...

I am half kidding.. The other half, well I guess I'm not.

M
 

NeverEnough02

Seaman
Joined
Feb 12, 2008
Messages
62
Re: 1995 5.8 Volvo/Penta

Ya, its a rough area for things like that. Is there a boat carfax? A survey would let me know everything but I was just wondering for future reference. It could have been a boat bought with insurance money after 1992's Andrew.
 

mcleaves

Chief Petty Officer
Joined
Sep 15, 2003
Messages
521
Re: 1995 5.8 Volvo/Penta

Ya, its a rough area for things like that. Is there a boat carfax? A survey would let me know everything but I was just wondering for future reference. It could have been a boat bought with insurance money after 1992's Andrew.

Or bought after any big storm over the past few years..

Anyhow, there ARE a couple service out there, but I don;t know anyone who has used them. I seem to recall they weren't all that reliable. I think a magazine did an analysis on them when they first hit the market and the results were mixed.

As for the ECMS, the ones on the Fords are known to crap out from time to time. Used ones hit ebay quite often as people retire the engines and they move quick. That means people are buying them. And while dcg9381 is right they are designed to have very low failure rates (I worked on the software development for the GM/delco auto computers for most of the 90's), I think the marine ones are exposed to more beatings both in terms of the wet environment and shock.


But if they were prone to failure they'd never make it in this market, so I agree they usually hold up fine. But they do fail. On a 13 year old boat, doesn't surprise me.
 

NeverEnough02

Seaman
Joined
Feb 12, 2008
Messages
62
Re: 1995 5.8 Volvo/Penta

Or bought after any big storm over the past few years..

Anyhow, there ARE a couple service out there, but I don;t know anyone who has used them. I seem to recall they weren't all that reliable. I think a magazine did an analysis on them when they first hit the market and the results were mixed.

As for the ECMS, the ones on the Fords are known to crap out from time to time. Used ones hit ebay quite often as people retire the engines and they move quick. That means people are buying them. And while dcg9381 is right they are designed to have very low failure rates (I worked on the software development for the GM/delco auto computers for most of the 90's), I think the marine ones are exposed to more beatings both in terms of the wet environment and shock.


But if they were prone to failure they'd never make it in this market, so I agree they usually hold up fine. But they do fail. On a 13 year old boat, doesn't surprise me.

Good to know. I know the boat wasnt bought after any storms, the person who traded it in bought it brand new. The dealer had the paperwork. Who knows what happened in between those times.
 
Top