Volvo 5.0Gi Overheat from Bad Impeller

[cparkhorn]

Background:
Engine Information:
Volvo Penta 5.0Gi PEFS 250HP
Engine Serial 4012014137
3869057 (Not sure what this number is)

Transom Assembly
TSK SX-M

Drive Unit
SX-M I 60

It is an I/O and the original engine in the boat which is a 2000 (not relevant I believe) and the engine looks black (could be considered charcoal but looks black to me)

I pay marina to winterize every year and assumed the impeller would be replaced, it is not and hasn't been since at least 2003 or earlier (7 years at minimum).

Engine overheated and started to beep, actually cut out on me to idle. I researched and checked the impeller, half of one paddle, all else is gone. Really bad. I replaced it and ran it over the 4th weekend. I'll need to flush the cooling system and am looking at all the diagnostics that Don S. has put out there.

The engine is almost always running at 175, jumps up some at times. If I go to neutral and sit for 10 seconds and then get up on plane the temp comes back down to 175. I'm thinking that might indicate blockage from pieces and they settle and provide room and water moves and cools it down, just a guess.

Questions:

1. In looking at the diagnostics there is a way to attach a garden hose to the hoses in the cooling to flush them out. Am I seeing that correctly in the pictures? Where do you get such an attachment or is it a homemade type thing.

2. I'm not seeing what temp that engine should run most of the time. I've seen comments about 160 degree thermostats, but I'm not sure if that means my gauge should always read 160. Is 160 the number, or is 175 consistently correct?

3. If I purchase a new thermostat does it come with the O Ring etc or do I need to purchase separately?

4. The bracket that goes to the Raw Impeller Assembly, the tip that sits between the inbound and outbound tubes has a bunch of black grease on it. I'm not sure if it is supposed to be there, but if not I'd love to clean it all off, it's a nightmare of a mess and is getting everywhere, I'm spending more time cleaning grease off tools, seats, carpet etc, than working on the boat.

Thank you for any help, I apologize if I've left anything out. I couldn't find any posts that answered after a long time searching. Any suggestions or things to look for when doing this (tips) would be appreciated. I'll be doing it myself from now on to make sure it's done at least every other year.

 

[Kainon]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Black Engine ? VP used Red/Orange Alot.. did someone replace with a Reman'd ? Or Mercruser BLock ? or painted it black ? Oh well..

1. . Homemade.
2. 160 ( +- 10% Inaccurate Gauges, sender connection etc.. )
3. That would sometimes depend on the brand you buy.
4.. I dont think that's grease.. sounds like Accessorie belt is wearing.
5. Changing Impellers from what i've seen isn't part of winterization needs, either is changing engine or outdrive oil, that would usually be an "extra".. and should've been mentioned by both parties at least.

Check the Adults Only section for some great Winterization Tips.

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Thanks for the feedback. I say black block, but from 1994 to 2000 it says they were charcoal, so that must be the actual color, it looks black to me. Original owner, So I'm very sure that's the original Volvo Penta Engine Block.

 

[KJSmitty]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Background:
Engine Information:
Volvo Penta 5.0Gi PEFS 250HP
Engine Serial 4012014137
3869057 (Not sure what this number is)

4. The bracket that goes to the Raw Impeller Assembly, the tip that sits between the inbound and outbound tubes has a bunch of black grease on it. I'm not sure if it is supposed to be there, but if not I'd love to clean it all off, it's a nightmare of a mess and is getting everywhere, I'm spending more time cleaning grease off tools, seats, carpet etc, than working on the boat.

Thank you for any help, I apologize if I've left anything out. I couldn't find any posts that answered after a long time searching. Any suggestions or things to look for when doing this (tips) would be appreciated. I'll be doing it myself from now on to make sure it's done at least every other year.

The bracket holding the impeller housing shouldn't have any "grease" on it. It should have a black rubber cover where it goes between the in/outlet however. If it is actually grease/oil, I would be looking for where it came from. Front crank seal, power steering pump? Did someone possible put grease on it to keep it from squeaking? Who knows.

As for the impeller and "winterization," like you, prior to doing it myself, my VP shop would recommend/do it every spring. Heck, I put a whopping 15 hours on a new one last year and found it torn when I removed it last fall. It's a cheap $26 part and easy to replace.

Good luck.

 

[dannyual767]

Re: Volvo 5.0Gi Overheat from Bad Impeller

4. The bracket that goes to the Raw Impeller Assembly, the tip that sits between the inbound and outbound tubes has a bunch of black grease on it. I'm not sure if it is supposed to be there, but if not I'd love to clean it all off, it's a nightmare of a mess and is getting everywhere, I'm spending more time cleaning grease off tools, seats, carpet etc, than working on the boat.

I replaced the original impeller on my 2004 Stingray (Volvo 5.0GL) this spring. Like yours, mine had the black stuff. It wasn't grease, though. It was a nasty, sticky, gooey residue. Kinda like liquefied rubber. It had to have come from that rubber cover because mine was in terrible shape. It was all distorted, slimy and unusable. I replaced it with a piece of old bicycle inner tube .

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Okay, the rubber glove makes sense. I'm guessing that it melted into a mess, grease was the best explanation, but it's a nasty sticky grease.

Is the glove necessary? Looking at Volvoparts diagram it looks like it might be called a "Stop". I'll have to look at replacing that separately, so I'm not sure if I need to rig up some sort of rubber cover until I get the replacement part.

I'm very confident it wasn't grease from somewhere else, it was very specifically on the tip of that bracket, the rubber glove makes perfect sense.

 

[rodbolt]

Re: Volvo 5.0Gi Overheat from Bad Impeller

that black goo is the rubber stop dissolving,dunno why but they do and its nasty.
is yours closed cooling or raw water cooled?
is this salt water use or fresh?
from abot 1994 to about 2003 volvos were charcoal grey.
cant remember and unless I am painting it its mostly irrelavent.
closed cooling typically runs in the 170 to 180 range.

 

[jclarke2899]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Background:
Engine Information:
Volvo Penta 5.0Gi PEFS 250HP
Engine Serial 4012014137
3869057 (Not sure what this number is)

Transom Assembly
TSK SX-M

Drive Unit
SX-M I 60

It is an I/O and the original engine in the boat which is a 2000 (not relevant I believe) and the engine looks black (could be considered charcoal but looks black to me)

I pay marina to winterize every year and assumed the impeller would be replaced, it is not and hasn't been since at least 2003 or earlier (7 years at minimum).

Engine overheated and started to beep, actually cut out on me to idle. I researched and checked the impeller, half of one paddle, all else is gone. Really bad. I replaced it and ran it over the 4th weekend. I'll need to flush the cooling system and am looking at all the diagnostics that Don S. has put out there.

The engine is almost always running at 175, jumps up some at times. If I go to neutral and sit for 10 seconds and then get up on plane the temp comes back down to 175. I'm thinking that might indicate blockage from pieces and they settle and provide room and water moves and cools it down, just a guess.

Questions:

1. In looking at the diagnostics there is a way to attach a garden hose to the hoses in the cooling to flush them out. Am I seeing that correctly in the pictures? Where do you get such an attachment or is it a homemade type thing.

2. I'm not seeing what temp that engine should run most of the time. I've seen comments about 160 degree thermostats, but I'm not sure if that means my gauge should always read 160. Is 160 the number, or is 175 consistently correct?

3. If I purchase a new thermostat does it come with the O Ring etc or do I need to purchase separately?

4. The bracket that goes to the Raw Impeller Assembly, the tip that sits between the inbound and outbound tubes has a bunch of black grease on it. I'm not sure if it is supposed to be there, but if not I'd love to clean it all off, it's a nightmare of a mess and is getting everywhere, I'm spending more time cleaning grease off tools, seats, carpet etc, than working on the boat.

Thank you for any help, I apologize if I've left anything out. I couldn't find any posts that answered after a long time searching. Any suggestions or things to look for when doing this (tips) would be appreciated. I'll be doing it myself from now on to make sure it's done at least every other year.

I too have a charcoal motor, and from what I understand, it was during their joint venture with OMC. It has made it a little tough for me to find parts, as some parts listed on the volvo penta website are not correct, and now that OMC is out of business, it doesn't help matters.

If you have the attachment on the side of your motor for flushing, you can normally hook a garden hose directly to it. My manual which covers a lot of motors says "All engines covered here utilize a 160F thermostat except the 7.4L/8.2L engines which use a thermostat rated at 140F, or models with a closed cooling system which generally use a 170F thermostat. I'm not sure of the specifics of your engine, but your manual may give you more precise. The key I found was getting the right manual as my motor says Volvo Penta all over it, but it is an OMC manual that is right for mine. Make sure the model number of your engine is the exact same as the manual you are using.

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Thank you for the information. I'm driving up tomorrow to trailer the boat and bring it home to work on, I'll update.

 

[dsiekman]

Re: Volvo 5.0Gi Overheat from Bad Impeller

I had a similar issue with the "black goo". As noted it was the rubber stop that had melted when my port engine started overheating. My mechanic tells me it needs to be there to stop the pump from walking and tearing itself up. It was only a couple bucks but he also said a piece of heater hose will work in a pinch.

A couple years ago I had an overheating issue with my merc 7.4. Impellor was fine but no water in the top end. Turned out to be most of an impellor that had torn itself into pieces had jammed itself into the oil cooler. The previous owner or his mechanic had evidently not gone looking for the missing vanes. Quality. The oil cooler is a very small passage, so I would start there.

Good luck!

 

[dsiekman]

Re: Volvo 5.0Gi Overheat from Bad Impeller

By the way, I have the same engines, raw water cooled, and mine run about 165. Not sure if that is the right number, but they match!

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Perfect I'll look at replacing the boot.

I'll be doing a full flush as much as possible, I'm sure there are pieces all over in there restricting the flow. Sounds dumb, but changing the impeller was an option that the marina offered and I said yes, they thought no, should have just done it myself from the get go that way I know it's done right.

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Update:

Got some direction from the Parts guy at Marina as well. I took off the Thermostat Housing and bam, tons of old impeller. Not sure how any water at all got through, so hopefully this fixes my overheat issue.

While I was at it I went up and got a new thermostat, O Ring and Gasket. I ran it on muffs and it stayed about 170 or so, but my issue only really came up when at high RPMs after replacing the impeller. I'm going to drop it in the lake and "hopefully" confirm all is well, and have a beer (no more than 2 ha). From now on I change the impeller myself every year.

Thank you very much for the information and help.

 

[cparkhorn]

Re: Volvo 5.0Gi Overheat from Bad Impeller

Ran the Volvo 5.0 Gi all weekend wakeboarding, you name it. Never got over 170. It got to a spot and stayed all day.

Huge help from everyone thanks.