Running hot and low oil pressure

[awesomesteven]

Finally got it running!

'86 sunport - 351

But now its running hot and it is showing I have low oil pressure. I know I have enough oil - I check the dipstick. I have a new impeller and I can see water coming out of yhe exhaust.

Any ideas where I could start?
12292

[Jetlink]

Probably a sensor/sending unit issue or a gauge issue.

[awesomesteven]

How hot are the manifold risers supposed to get? Should you be able to put your hand on them and not get too hot the touch?

[Salty87]

How hot are the manifold risers supposed to get? Should you be able to put your hand on them and not get too hot the touch?

yes, for a few seconds. go get an infrared temp gauge so you can check temps at various spots.

[DAFF]

Looks like there is a issue with the water supply. Pull off a hose near the exhaust manifold water should gush out with a torrent. My guess is you installed the impeller so it is pushing rather than sucking water. Most of us have done this me included. Oil pressure can run on the low side at idle especially when the engine is warm, at 2000RPM and 20lbs pressure then there is some real issues.

[Jetlink]

Except that if the impeller is installed incorrectly they won't get any water at the exhaust outlet which I believe they said they were. That is why I believe this is either a sending unit issue or a gauge issue.

[DAFF]

My bad reading too fast. Water out of the exhaust and hot temps sound like a lazy thermostat which is sticking closed.

[awesomesteven]

Probably a sensor/sending unit issue or a gauge issue.

For the oil pressure right? Would this be the right part? Could I pick this up at NAPA?
http://www.skidim.com/prodinfo.asp?number=R020001


Looks like there is a issue with the water supply. Pull off a hose near the exhaust manifold water should gush out with a torrent. My guess is you installed the impeller so it is pushing rather than sucking water. Most of us have done this me included. Oil pressure can run on the low side at idle especially when the engine is warm, at 2000RPM and 20lbs pressure then there is some real issues.

I just tried this. I had a hose attached right below the water strainer and it seems to suck the water out just fine but if I use the hose and fill a bucket and let the pump draw off that the bucket overflows and it doesn't seem to draw any water.

So this confirms that I have the pump upside down, right? Why wouldn't it push the water out with the hose directly attached?I would have turned it but my girl got on me for it being too late and not wanting to wake up the neighbors. haha

[Jetlink]

Have you replaced the impeller recently? Also, for the oil pressure switch, as long as you have one for a "Ford 351" Napa will work, pretty sure that's where I got mine from.

[DAFF]

Put the intake hose into the pale of water. Remove the upper hose and spin the pump with your hand using the pully. Determine which way it has to spin to pull water from the pail and check to rotation of the engine by tapping the key. If these are both spinning in corecation then you will have water getting sucked up from the lake.

[awesomesteven]

Have you replaced the impeller recently? Also, for the oil pressure switch, as long as you have one for a "Ford 351" Napa will work, pretty sure that's where I got mine from.

Looks like another trip to Napa. First name basis at this point. haha.
Yea, I just bought the impeller about a month ago.


Put the intake hose into the pale of water. Remove the upper hose and spin the pump with your hand using the pully. Determine which way it has to spin to pull water from the pail and check to rotation of the engine by tapping the key. If these are both spinning in corecation then you will have water getting sucked up from the lake.

I'll have to give this a shot tomorrow.
Which one do you mean by "upper hose"?

[Jetlink]

Do me a favor, go out to your boat and snap a few pics of your impeller housing, mainly where the hose inlet and outlet is. The outlets need to be closest to the center of the engine for proper rotation.

[DAFF]

Perhaps a sticky write up for the correct and incorrect orientation for the pump with pictures. This seems to be a very common issue and is very EZ to get it backwards...

[awesomesteven]

http://img.tapatalk.com/d/13/06/13/u5e3azy3.jpg
That's from the backside

http://img.tapatalk.com/d/13/06/13/qabepyra.jpg
From the side.

[Jetlink]

You got the orientation correct so unless your impeller took a dump on you that's not the issue with regards to cooling.

[wotan2525]

With the intake hose in the bucket you should def. feel a strong SUCKING on the hose (even at idle.) On my boat, my hose cant even keep up with what the pump needs supplied.

It's possible that your pump is warn or there is some kind of blockage. Blockage is the cheapest/easiest to troubleshoot. Take off each cooling line and flush it out to try and get old pieces of impeller out. Let's try and get this flowing before we start messing with the thermostat or anything else.

Let us know what you find and if that improves things.....

[DAFF]

When you removed the old impeller was there any pieces missing?? If so that's your flow blockage!!

[awesomesteven]

With the intake hose in the bucket you should def. feel a strong SUCKING on the hose (even at idle.) On my boat, my hose cant even keep up with what the pump needs supplied.

It's possible that your pump is warn or there is some kind of blockage. Blockage is the cheapest/easiest to troubleshoot. Take off each cooling line and flush it out to try and get old pieces of impeller out. Let's try and get this flowing before we start messing with the thermostat or anything else.

Let us know what you find and if that improves things.....


When you removed the old impeller was there any pieces missing?? If so that's your flow blockage!!

There were no pieces missing from the impeller or the housing. The boat did sit for about 1.5 years before I bought it so something could be suck in there. I have heard of horror stories squirrels and birds getting in throug the exhause and nesting there! Probably not that. but since it's not sucking too much water (if any) I guess there has to be some kind of blockage. I guess I'll have to go through each hose and the exhaust to make sure.

[wotan2525]

There were no pieces missing from the impeller or the housing. The boat did sit for about 1.5 years before I bought it so something could be suck in there. I have heard of horror stories squirrels and birds getting in throug the exhause and nesting there! Probably not that. but since it's not sucking too much water (if any) I guess there has to be some kind of blockage. I guess I'll have to go through each hose and the exhaust to make sure.

Let's start with something easier -- it's very strange that the hose is pushing water into the engine but that the pump isn't pulling water into the engine.

Take the top and bottom hoses off of the pump. You should be able to feel it "suck" on the bottom hose even if you just turn the pulley over by hand. If not, it's time to take that sucker apart -- it's possible that your new impeller is already fried.

[awesomesteven]

Could it be the seal on the water strainer?

[Jetlink]

Could it be the seal on the water strainer?

Possibly, but lets focus on isolating the raw water pump first.

[awesomesteven]

Ok. So I started with the impeller. Just like new. I put a cup of water on the bottom of the pump (no hose) and turn it by hand and it starter sucking up water.

Next, I disconnected the house that runs from the pump to the strainer made sure it was clean. Good. Hooked it up to the pump on one end and a bucket of water on the other. I bumped the engine and after a few bumps I was drawing water. Good here.

Next I made sure the hoses that are on the stainer were good. They were. This time when I put the bucket of water at the strainer and bumped the engine I got nothing. No water is being drawn from here.

[Jetlink]

How's the seal on the strainer? Is it looking tired? Also, is the strainer upstream or downstream from your trans cooler?

[awesomesteven]

How's the seal on the strainer? Is it looking tired? Also, is the strainer upstream or downstream from your trans cooler?

The seal for the strainer looks not so great.

The trans cooler is downstream from the strainer. Strainer -> trans cooler -> water pump

[Jetlink]

Can you isolate the strainer from the supply chain? I'd think that you found the issue with the strainer gasket being faulty and allowing the introduction of air into the system.

[awesomesteven]

Yea...new seal for the strainer. That's probably why its not sucking up the water.

But that wasn't the issue with the temp. I did it again and everything ran fine. I realized that I didn't have enough water pressure on the hose.

On to the next thing....