Oil pressure problems

michaelvb95

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I recently had a remanufactured VP 5.7 Gsi put in my boat back in September . I took the boat out twice so far this year. I noticed this last time the oil pressure gauge was pegging at 3000 rpm. Since my gauge doesn’t have actual numbers, I hooked up a manual gauge. Tells me I’m idling at 60psi and around 85-90 at anything above 3000rpm. I then decided to change the oil and it came out looking dark and smelling a bit like gasoline. Otherwise the boat seems to be running fine. Any ideas?
 
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alldodge

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Who ever rebuilt the motor must have put a high pressure pump in. Nothing wrong with a high pressure pump but if used the bearing clearances need to be a bit different. How much HP was the motor said to have, stock or higher?

Do you know what oil was used?
 

alldodge

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Pretty much stock HP range
With a hp pump its probably increasing the heat because the pump is generating heat because of the standard clearances.

I'm thinking it could use a oil cooler or if it has one a larger one. Most likely if you had a oil temp gauge it would be over 300* and is burning the oil.

Had a 530HP motor with hp pump and wondered why the oil was turning black after about one run. Installed a Temp gauge from the oil filter head and found the oil getting to hot. Installed a larger oil cooler and larger oil lines which fixed the issue
 

michaelvb95

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Pretty much stock HP range
With a hp pump its probably increasing the heat because the pump is generating heat because of the standard clearances.

I'm thinking it could use a oil cooler or if it has one a larger one. Most likely if you had a oil temp gauge it would be over 300* and is burning the oil.

Had a 530HP motor with hp pump and wondered why the oil was turning black after about one run. Installed a Temp gauge from the oil filter head and found the oil getting too hot. Installed a larger oil cooler and larger oil lines which fixed the is
Pretty much stock HP range
With a hp pump its probably increasing the heat because the pump is generating heat because of the standard clearances.

I'm thinking it could use a oil cooler or if it has one a larger one. Most likely if you had a oil temp gauge it would be over 300* and is burning the oil.

Had a 530HP motor with hp pump and wondered why the oil was turning black after about one run. Installed a Temp gauge from the oil filter head and found the oil getting to hot. Installed a larger oil cooler and larger oil lines which fixed the issue
Do you think I run a risk of damaging anything if left as is till I can get it into a shop next month?
 

Bondo

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I recently had a remanufactured VP 5.7 Gsi put in my boat back in September . I took the boat out twice so far this year. I noticed this last time the oil pressure gauge was pegging at 3000 rpm. Since my gauge doesn’t have actual numbers, I hooked up a manual gauge. Tells me I’m idling at 60psi and around 85-90 at anything above 3000rpm. I then decided to change the oil and it came out looking dark and smelling a bit like gasoline. Otherwise the boat seems to be running fine. Any ideas?
Ayuh,..... Welcome Aboard,..... Not to take away from this conversation, as AD might be onto something, But,......
How long after a cold start did you see these pressures,..??
Dead cold oil, always runs at high pressures, til it warms to operatin' temps,....
'n to answer yer last question, shoot the oil filter with a temp-gun,.....
If under 280 / 300*, you might be Ok,..... over 300* is pretty damn hot even for motor oil,....

You most definitely want to contact the motor builder, asap though,.....
 

michaelvb95

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Ayuh,..... Welcome Aboard,..... Not to take away from this conversation, as AD might be onto something, But,......
How long after a cold start did you see these pressures,..??
Dead cold oil, always runs at high pressures, til it warms to operatin' temps,....
'n to answer yer last question, shoot the oil filter with a temp-gun,.....
If under 280 / 300*, you might be Ok,..... over 300* is pretty damn hot even for motor oil,....

You most definitely want to contact the motor builder, asap though,.....
From what I understand they only replaced the engine block , everything else was just taken off and put back on. Kind of annoying for 7000$

Mechanic who put the new engine in said he’s not worried about the pressure. It may just be due to clearances. I’m sort of new to boating and by no means am I very educated on boat engines, so I’m not sure what he means by that. I know some basics from growing up working on cars but boats seem like a whole different world.

Is shooting it with a temp gun really an accurate reading?
 

alldodge

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Is shooting it with a temp gun really an accurate reading?
Accurate enough to get an idea on the oil filter. See 300+ is not good, under 300 could be ok. Check after a good run and don't let it idle a long time. After the oil filter is what the bearings see

Run some 10W40 or 15W40
 
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