Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

[beauty754]

I have a 1998 Regal 2500 LSR with the 5.7 motor in it. Last summer I fought and overheating problem that I couldn't get fixed. It kept climbing to 200 degrees in temperature, where it would then go into engine saver mode. The motor wouldn't die it would just stop whatever RPM it was at and go to an idle. I can troll and idle all day long at around 160 degrees but when I get on the throttle a little bit it takes about 45 seconds to climb to 175 degrees and about a minute after 175 degrees it climbs to 200 degrees and dies.

I finally caved in and took it to my local Regal dealer and asked their service department to take a stab at it. They replaced the impeller( which was almost all gone), thermostat (which was stuck shut with corrosion) , temp sensor (which was found on their coding computer to be throwing a code), and even pulled a softball size melted piece of rubber out of my outdrive, they told me it was a rubber flapper used for exiting circulated water out of my motor. Here is the problem though they only hooked it up to the rabbit ears at the shop and didn't test drive it on the water. So when I went boating again last Saturday it immediately overheated to 200 degrees and went into engine saver mode. With my hope dwindling I am asking any of you for advice and assurance. They said they have went through all of the lines and made sure flow was good, but now that it overheated "they are double checking once again".

my Questions:

1. what is good running temperature for these motors?
2. is there anything else to check that could cause this much of an overheating issue?
3. should I just sink the damn thing and collect insurance? (i'm only joking, just wanted to add some humor)

All ideas and advice is much appreciated.

 

[killer71]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

Just curious how you get it out of engine saver mode as I recently had similar problem?

 

[Don S]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

Raw water cooled engines shouldn't run over 170-175?. When it hits 180? you should be wondering why.

Have the exhaust risers been pulled and inspected for clogged passages. Might want to separate the drive and see if the big rubber seal around the pickup tube is all burned up. If it is, the raw water pump will suck air and not water.
Sounds like your engine and cooling system is suffering from some serious neglect.

 

[beauty754]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

The boat has been seriously neglected, I bought it last year in moderate condition for $3,500. I had no clue it would be this much trouble. I will check with the mechanic and see what he finds out.

 

[MNBrent]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

There is a VP overheat manual that Don could hook you up, or you could find by thread search with that helps step through the diagnosis. There is also a shorter overheat isolation walkthrough in the VP engine service manuals.

I'm currently in the process with my new to me 2004 VP 5.0. Fun stuff right!!

 

[wkb2460]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

You might also check the engine circulating pump.

 

[bvh]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

Could be one of these.
1. Blocked manifolds or risors due to corrosion. Overheat under load
2. Bad seal in outdrive between pickup and sea water pump allowing it to suck air on plane, but not submerged.
3. The rest of the impeller got stuck in block, manifolds, or risor.

Also, there may be damage to the head gasket or warped heads. It sounds like it overheated pretty good to fry the flapper

Is there any burnt paint on block or manifolds? Does the oil look good and water free?

 

[beauty754]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

Could be one of these.
1. Blocked manifolds or risors due to corrosion. Overheat under load
2. Bad seal in outdrive between pickup and sea water pump allowing it to suck air on plane, but not submerged.
3. The rest of the impeller got stuck in block, manifolds, or risor.

Also, there may be damage to the head gasket or warped heads. It sounds like it overheated pretty good to fry the flapper

Is there any burnt paint on block or manifolds? Does the oil look good and water free?

They are looking into those issue now. Starting with taking the exhaust manifolds and risers off. There was no water in the oil or signs of paint burnt off the exhaust manifolds. What would a circulating pump do if it was out? Because I'm at 150 degrees while trolling and idling.

 

[wkb2460]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

If the impeller is worn down it won't circulate as much water, especially when it needs more at higher speeds.
At lower speed it might move just enough water to cool you down.

 

[beauty754]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

If the impeller is worn down it won't circulate as much water, especially when it needs more at higher speeds.
At lower speed it might move just enough water to cool you down.

I already replaced the impeller or are there more than one impeller?

 

[wkb2460]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

There's the raw water impeller and the circulating pump impeller. Two seperate impellers

 

[Maclin]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

Generally, overheating at lower speeds or even idling indicates raw water impeller, overheating only at higher speeds indicates a blockage after the raw water impeller. Overheating at speed then cooling down when returning to idling or no-wake speed can indicate an air leak in the drive water pickup plumbing.

The engine circulating pump is a different type of unit than the raw water pump, and the impeller there does not touch anything but water and does not wear down. For most engines it is not considered a serviceable item, and if it is a proper marine unit then it should have a long life and outlast the shaft seal and/or bearings. When that pump is acting up then it will be leaking water from the weep hole on the snout just behind the pulley.

 

[scot9055]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

a friend of mine had taken a water hose and connected to his engine and ran it for while this spring before taking it out. When he was finished he didnt put it all the way on and it ran hot, Im guessing it was sucking air in and not the amount of water it needed. I asked him exactly what have you done since last year he said hooked water to it and ran it yesterday so I looked and yep cap was loose. Tightened it up and whalla perfect ever since.

 

[Don S]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

A trip to the forum stickies would be a good thing. Stickies are there for a reason, and shouldn't be ignored.

But new members never seem to look at stickies. Why is that?

 

[janpoe]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

I have 1994 351 omc/volvo penta. Everytime I first put the boat in the water and launch it then engine overheats
to 220-230. it takes me quite a while of reving, turning off, restating, reving etc. Eventually it does cool down to
120-140 and stays that way the rest of the day. its only on the initail lauch that I have this issue. Its as if
it take excessivly long to prime the system. The impleller has been replaced but still has this issue. Any ideas??
I have not checked the thermastat yet but I am going to look at that this weekend....any other ideas??

 

[Shark_bait99]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

I have 1994 351 omc/volvo penta. Everytime I first put the boat in the water and launch it then engine overheats
to 220-230. it takes me quite a while of reving, turning off, restating, reving etc. Eventually it does cool down to
120-140 and stays that way the rest of the day. its only on the initail lauch that I have this issue. Its as if
it take excessivly long to prime the system. The impleller has been replaced but still has this issue. Any ideas??
I have not checked the thermastat yet but I am going to look at that this weekend....any other ideas??

I have the same problem if i dont run near wot for about 30 sec when i cast off. The po told me to do this or the engine overheats. Airlock in the raw water system he claimed. Mines a 2004 5.7gi-e so I am not sure if it applicable to you but worth a shot. I have just opened a thread asking why I need to do this. I only know it works.

 

[Thalasso]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

You two need to start your own thread. You might get an answer.janpoe & Shark-bait99

 

[Shark_bait99]

Re: Volvo Penta 5.7 GXI OVER HEATING replaced everything! PLEASE HELP

You two need to start your own thread. You might get an answer.janpoe & Shark-bait99

I did open a new thread... and stated that in my previous post...

I have just opened a thread asking why I need to do this. I only know it works.