Temperature Levels - Striper Talk Striped Bass Fishing, Surfcasting, Boating

bloocrab · 06-13-2003, 08:44 AM

Ok...here we go again.

I finally got my boat back, but it still has issues

It's still getting TOO HOT !!!

What temperature would be considered dangerously HOT??? I'm so freakin GREEN to this boat stuff...

My temperature guage takes readings from 0 - 240. If I run the boat at 2200 RPMs or more, for about 7-8 minutes....she almost gets pinned at 240 degrees.

I then have to slow it down to about 900 RPMs in order to get the temperature back down to around 180. It really sucks having to slow down to turtle speed every 10 minutes for 10 minutes.

So what do you think? What's the healthy normal temperature for an I/O OMC with a 350 engine????

...hot or not, I won't be stopped

bloocrab · 06-13-2003, 08:47 AM

...for the record,

I've already replaced the Water Pump in the leg. I already replaced the Risers . I already replaced the hoses. I just had the lower leg rebuilt. I removed the thermostat already too. The water pump on the engine looks newly replaced too..

Should I just run the witch until she pops? Or proves that she can't be popped??...

Any guesses???

MakoMike · 06-13-2003, 10:17 AM

Bloo,
Normal should be in the 180-200 range. Don't push it or you'll warp a head, biiiig trouble. Is the engine fresh or raw water cooled? Have you checked your strainers?

bloocrab · 06-13-2003, 02:38 PM

..Mike,

Thanks for the reply.

Yes, the strainers were clear and it's RAW water cooled. You would think it's something simple.....but I must be retarded because she keeps getting HOT. I don't mind if she's HOT looking, but I don't want her HOT running...

My gut feeling tells me that the pump doesn't work fast enough for the engine. If I stay at a low RPM, she's fine...but as the revolutions increase....the water that is being drawn in, just isn't enough to keep her cool. <<<???>>> Or, maybe the water doesn't exit out fast enough. Maybe the HOT water is staying in the engine too long. We did the hose test and it passed fine. (disconnected the hose and counted the time it took to fill a 5 gallon bucket)..so it makes it seem like the water intake/output is ok, UNTIL...you get on her!!!

...when you see that boat out there that keeps looking like it's running out of gas, come over and say hello.

fishaholic18 · 06-13-2003, 04:16 PM

Bloo, are you sure the guage and the sensor are reading correctly? I'd rig up another guage and sensor to be sure before you go too nuts.

NilsC · 06-13-2003, 04:33 PM

We used to have a water pressure gauge on the pressure side of the water pump. (App. 35yrs ago) The one we used had a triggered switch when the water pressure dropped light and horn came on (most of the time this happened with crap blocking the RAW water intake/strain.
One time we had multiple problems on the same day caused by the low-pressure line collapsing and restricting the flow during high RPM’s on the motor. The shop sad this was caused from intake screen to small for the diameter hose and the new water pump to strong (Water pump was mechanical run of the fly-wheel)

I agree with fishaholic18, rig up another gauge and or add water pressure gauge. With a water pressure gauge you can see the drop in pressure as the impellers are worn.

Nils

NEXT2NUN · 06-13-2003, 06:36 PM

Hey bloo, When you replaced the risers were the manifolds clean inside,sometimes they get built up with scale.Take the ends off and clean out with a thin threaded rod. Another thing you can check.The gasket between the manifold and the riser. there is a difference between fresh and salt water cooled,fresh water cooled restricts or stops flow from the manifold to the riser with two gaskets and a stainless plate , salt water cooled only uses one gasket.Don't be afraid to check the sending unit and guage,Good luck let me know how you make out.

bloocrab · 06-14-2003, 03:58 PM

...thanks for the feed-back fellas.....I'm so fREaKin gREen!!!

...the web just got more tangled....

Goose · 06-14-2003, 04:23 PM

talkin bout feed back??

UserRemoved1 · 06-14-2003, 05:12 PM

COULD also be a warped head too, hot cylinder gas squeezin into the water jacket can do this...

nightfighter · 06-15-2003, 09:50 PM

Wow. Lotta guys gone through some chit with their boats I see.

Assuming not a cracked/warped head or more serious SNAFU, I would lean toward NilsC's diagnosis. Check age of intake,low pressure hose to be sure it's not collapsing when under higher RPMs. Swap the gauge too. I've had to do both before....sux, it's diagnosis by elimination in many a case. Just hope it doesn't take a whole season to be worry free when you leave the dock!

JohnR · 06-16-2003, 06:11 AM

It was hinted in here - run the boat til it gets hot with the engine cover off (don't fall in!) & make sure that none of the cooling hoses collapse at higher RPMS when it get's hot. A lot of boats have metal coils inside the hose to prevent just this from happening.... You said you removed the T-Stat and it still does it?

bloocrab · 06-16-2003, 07:16 AM

Nun - when we replaced the risers, there was some flakey particles inside..we cleaned it very thoroughly. Rust-like stuff...I'm guessing that's the "scale" you speak of. We also had the guage tested and it was fine. The hoses get extremely hot but do not appear to be blocked or restricted (I replaced them at the beginning of the season). Yes, John..the thermostat is no more. I'm beginning to think I belong on shore

and these are just aggravating ways to remind me of that...

Average cost of making it an Outboard?

MakoMike · 06-16-2003, 07:39 AM

Bloo,
This is a difficult probelm, since it could be due to so many things. You said you replaced the hoses at the beginning of the year and checked the strainers. I assume the seacock is fully open? Next thing I would check would be the water pump impeller.

JohnR · 06-16-2003, 08:55 AM

How did the bucket test go?

Here is some decent info - probably not what you need but a decent foundation - look at the descriptions for overheating

http://www.boatered.com/forum/topic....s=hot,high,rpm

NEXT2NUN · 06-16-2003, 07:42 PM

Bloo, the only other thing I can think of is the block is loaded with rusty scale.There should be a drain plug on both sides of the block under the exaust manifold. Pull the plugs and see if water flows out.If not fish around with a small piece of wire and see if its loaded with rust. If it is pop out all the freeze plugs and flush all the crap out.Make sure you replace with brass freeze plugs. If the boat stays in the water with salt water cooling this is fairly common with older engines. Im assuming the engine runs fine, if it is skipping or running rough when it heats up you probably have a cracked head orbad head gasket.

bloocrab · 06-16-2003, 10:36 PM

Maco...your right.....it could be the simplest thing, we just can't pinpoint the bastage. When I say we, I mean, (me & the crew @ Tripp Marine, Wesport Ma) are having a hell of a time with this pig.

I've replaced the following: <in this order>

Complete Engine Tune-up
Replaced all hoses on engine.
Replaced Thermostat
Removed Thermostat
Did the bucket test (making sure it was pumping the water as it shoud be)
Tested the Sensor Guage
Took an actual temperature reading from the engine itself
Replaced Risers & Riser Elbows & thouroughly cleaned the inside cavities out
Replaced WaterPump-Impeller Kit
Replaced the entire gear mechanism in the leg unit

Nun - when I had the risers replaced, I personally cleaned out the manifold cavities scraping any loose 'scale' from the walls. I'm pretty sure I got most of it, but you have a point...maybe due to it's age...it built up again or fell from spots I couldn't reach ??? The only problem with that theory (blockage) is that is doesn't overheat at a low RPM. So if it was being restricted, I'd imagine it would be restricted even at a low RPM level. My strongest guess is that the impeller doesn't draw enough water in at high speeds so it takes the hotter water longer to get out...but what do I know

I'm unfamiliar with the low pressure hose though??...two hoses pump in, two hoses pump out...which is the low pressure hose, the two that pump out??

The engine was running fine...last trip out, it stalled and hasn't started since. I'm afraid she may have seized up on me. I didnt' have the temperature pegged, but now she just won't turn over. I noticed the Battery gauge is now reading 0, telling me either the battery suddenly went dead by itself

or the engine drained it because it had seized up. I'm headed down tomorrow with 2 new batteries, I'm going to try a few more things...then she's coming out again...and back to $$$ Tripp's.

$%@$%@%^^&@%@#$%^&%^$$#T# BOATS!!!

PNG · 06-17-2003, 07:08 AM

Look at this way...

This fine craft is making you into a top notch trouble shooting mechanic

When your done you'll know her inside out

bloocrab · 06-17-2003, 08:36 AM

PasNGas...

I was under the impression that boats were like women....

Just when you think you know em'...they throw you a loop, that ya just can't figure out.

..on another note:

When I towed the boat back to the mooring, the boat that's moored parallel to mine...was 1/3 of the way in

(sinking that is)....could the marina be haunted??

...I spoke with the owner of the sinking boat, he decided to remove the plug while tied to his mooring...when the water started gushing in...he quickly put it back, incorrectly that is!!...how do you do that???...

the next day he came down to find the harbor master pumping water out. Good thing the HM is a consciencious dude, who cares...

..hey, at least his boat runs.

NEXT2NUN · 06-17-2003, 06:05 PM

Bloo, boats are woman. Just when you get em all dolled up and ready to show off they want to stay home. Reread my last post I think you should clean the engine block, not manifolds. I'm in Dartmouth if you need me.

Megabyte · 06-17-2003, 06:19 PM

Bloo, one more suggestion :-)

I've seen this happen when the water pump impellor "slips".
There is a lot less slip at low RPM's. As the RPM's increase there is more slip cause the impellor not to keep up the water flow.

Simple things:
Check to make sure the "key" to the water impellor / shaft was installed.
Check to make sure the impellor has been "spun" off the shaft. The rubber portion tore loose from the shaft portion.

Just 2 more on the list :-)

Raven · 06-17-2003, 06:55 PM

it would seem like you didnt go for a test drive with the mechanic aboard so he could hear and or see the problem...or perhaps your marina isnt beside the water? I would make sure they guarantee their work and not just hand over your boat and say bye- bye...when you first mentioned it -> first thing that came to mind was too rich a fuel mixture. i was driving a dump truck that had the choke cable broken and that made the fuel mixture so rich
that the tail pipe was red hot and people behind me called the fire department while i was driving it. Until it stalled that is.

kynan · 06-17-2003, 09:25 PM

i just got rid of a 91 omc 302.

I replaced the risers and manifolds as a set. That is what's advised, every 4 years in salt. Risers may look fine on one side, but removing them lets you see how the heads look as well.

Now, most thermostats open at 160. If I was running 180, that was hot. Good running temp is anything around 168 or below. 240 and you are cooking it....I hope you immediately shut down!

When i got that hot, it would take a lot longer than 10 minutes to cool down.

I also replaced all the hoses which wasn't that much. I would check for a loose belt , as well if you have a Cobra outdrive, there's a little hose in there from the pump that can get clogged...happened to me.

Now here's the good news, if the heads are the same between a 302 and a 350, I have my old set sitting on a shelf that I believe are good, that I'd let go for cheap, or for barter.

try the other options first. Don't keep running if it gets hot. Fire it up and let it idle for some time and see what happens. A simple measure absent a gauge is simply to rest your hand on the riser, they should get warm, ut not burn your hand. It's normal for one to be a tad warmer than the other.

bloocrab · 06-18-2003, 09:51 AM

Quote:

Now, most thermostats open at 160. If I was running 180, that was hot. Good running temp is anything around 168 or below. 240 and you are cooking it....I hope you immediately shut down!

I removed the thermostat a looooong time ago...and never had her running below 160>> unless I was just idling.

Quote:

When i got that hot, it would take a lot longer than 10 minutes to cool down.

About "immediately" shutting down, I found that when I immediately shut her down..it would take much much longer to cool and MUCH longer to restart the engine. If I kept her at a low idle (somewhere under 900 RPMs) she would cool down much much faster. Telling me that at lower RPMs everything was working ok.

It is a Cobra outdrive, but I'm not sure what "little hose" your speaking of. How would you normally clear out that hose? Or see that it was clogged? Does this hose lead to the intake on the bottom of the leg? All but the shell was replaced in the outdrive. Impeller Kit/Gears/Etc...I'd imagine that area was clear of debris.

As far as the risers getting hot, YEAH BABY!!...they sure would, and like you said...one would always get hotter than the other. The new hoses were also too hot for the touch after awhile. The hot water isn't getting out fast enough. Does this mean that it's not getting pumped in fast enough, OR...it's getting blocked on the way out??...lolol...I think the mechanic knows what he's doing...

...but no-one else would touch a 1974.

As far as the heads go, I don't know if they're compatible...but I'll keep it in mind. Thanks for the reply- and the offer -

MakoMike · 06-18-2003, 12:23 PM

Bloo,
The bucket test indicates that everything ws O.K. at idle, did you do it at higher RPMs? The thing about a slipping impeller sounds like it sould be right to me.

Mr. Sandman · 06-18-2003, 12:47 PM

The water pump is an easy check and fix....what about a head passage that is clogged...you mentioned you replaced the riser and manifold but the temp sensor is ususally screwed into the head...the temp you are measuring is either the engine block or head. If its not the pump it sounds to me like you have a restriction internal to the head which the pump can't push enough water thru at high speed. to keep her cool. The therms are probably wide open.

Salt water cooling is a nightmare I didn't know they still make that on inboards. I had a SWC "grey marine" 225 inboard once....what a nightmare. Repowered with a crusader 350ci fwc and ran for many years without problems.

240 is pretty damn hot (fw water boils at 220), you probably saw some serious steam out of the exhaust.

If the pump checks out you may have to have the heads boiled out.

good luck.
(don't forget ...short blocks are cheap)

bloocrab · 06-25-2003, 11:33 AM

Just wanted to thank you guys for your comments, tips, and advice. I just got word from the mechanic (Tripp Marine, Wesport Ma.

)...that he GIVES UP!!???...What's up with that? I've never heard of a mechanic "giving up"

I hate to discredit him, BUT!!...

He claims the lower gear unit stripped the upper gear unit and he has no clue as to why. He's afraid to go any further.

...I'm about to plant a flower above this money pit.

MakoMike · 06-25-2003, 12:30 PM

Bloo,
Sorry to hear that. The only mechanic that I know, whom I would recommend is in Montauk.

bloocrab · 06-25-2003, 11:10 PM

Thanks for the condolences Mike

...ya know, all kidding aside...I really don't get it. I mean...a nut is a nut is a gear is gear. I firmly believe that if that was my occupation, ONE WAY OR ANOTHER, something would work. He didn't even suggest to try and find an interchangeable out drive with limited modifications...he didn't even offer to overhaul it into a complete OutDrive PERIOD! I just don't get it. My boat must have haunted him in his dreams. ...yeah right.

...who knows what the future brings.

R.I.P. <<BLOOZCRUZ>>

capesams · 06-26-2003, 06:09 AM

gill bracket

an ob.......sorry to hear of your loss...I think he did his best...most would have taken one look at a c out drive an said sorry we don't touch them.....it's tough I know to get this news, but sometimes you just can't bring back the dead no matter how much money you through at it.....if you truly love that boat , look around for an up dated rebuilt motor an outdrive....best o luck with your second wife....