What are your engine temps? Mine seem high??

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-12-2006, 8:42 AM

I took out a 02 Mobius LSV for its first run this year and the engine temps seem high. After warm up the temps go to 220 and hold. Once i stop and start again it goes to below 180 and slowly increases back to 220 and holds. It wont go any higher but seems kinda high for me. Is this normal???

I just bought the boat and it only has 48 hours on it.

(wake_upppp) · (wake_upppp) **Join Date: Nov 2003** 03-12-2006, 9:08 AM

Mine runs around 180 to 190. 220 is a bit high if the reading is correct. Check impeller and raw water intake for blockage. If it's equiped with a raw water strainer, make sure it's clean and free of debris. The other thing you can do is run it out of the water off a fake a lake and make sure you're getting plenty of water flow out the exhaust.

akman 03-12-2006, 9:45 AM

In the middle of summer my engine temp stays around 160-170 tops.

(joe1975) · (joe1975) **Join Date: Jan 2006** 03-12-2006, 9:58 AM

sounds too high. Most likely the vanes on the impeller have worn down. you should at least check the impeller right away.

(yosquire) · (yosquire) **Join Date: Jun 2005** 03-12-2006, 9:58 AM

anything approaching 230 is melt down time. (speaking in terms of **AUTOMOTIVE** Chevy small blocks)

I agree with Sparky, In addition, and after following Sparky's advice first, you might want to check the thermostat.

One thing for certian, you have a problem some where.
http://www.moomba.com/owner_manuals/moomba_02.pdf
"Water Temprature: 160 degrees to 180 degrees for raw water systems..."

Personally, if I were you, I'd be shutting the boat off at 210+. Letting it cool for as long as you can. (20 minutes) Then driving it back to the trailer. What you don't want is a warped head or cracked engine block. 55 degree water is much more harsh to a 220 degree engine than when compared to a closed loop (automotive) cooling system where the water is ....say.... 210 degrees coming out of the raidiator.

(wakedad33) · (wakedad33) **Join Date: Oct 2005** 03-12-2006, 11:53 AM

Bid E, even though you only have 48 hr, the impeller is probably original and at least 3 years old. good chance that is your problem. Sparky's post brakes it down for all things to check. Did you have it winterized or do it your self?

(wakesetter101)

I just looked at the impeller by taking the cover off and looking at it with a mirror. Everything looks fine. Still feels soft and turns good with engine being bumped over. I dont think that is the problem.

(mikeski) · (mikeski) **Join Date: Aug 2003** 03-12-2006, 1:01 PM

Steam from the exhaust is often a better temperature indicator than the gauge on the dash. Small white puffs every now and then are OK, billowing steam is not. What is coming out of your exhaust.

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-12-2006, 1:36 PM

I am kinda scared to take it back out. The boat seemed to run fine at 220 almost like the gauge is not right.

But once you stop and take off on the boat it drops down to below 180 for a few minutes and then its back to 220 and holding.

(mobv) · (mobv) **Join Date: Jun 2002** 03-12-2006, 2:03 PM

Engine should go into limp mode (limit of 1000 rpm) around that temperature.

I had trash plugging the oil cooler once that caused high temp.

(will5150) · (will5150) **Join Date: Oct 2002** 03-12-2006, 3:02 PM

Change the oil, trans fluid- everything. and thinkg about having the block flushed. You may have some stuff plugging a water way in the block and creating excess heat- that's definitely too hot unless you're running a fresh water cooling system , for salt water use. 170 is the magic number.

nautique226 03-12-2006, 4:05 PM

Its possible its a faulty temp gage.

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-12-2006, 4:25 PM

To me the boat is running to good to be at 220 degrees. I dont hear any strange noises or any power lose.

(byrd) · (byrd) **Join Date: Dec 2005** 03-12-2006, 5:14 PM

Did you remove the impeller and look at it or did you just look at it after you pulled the plate off. The reason I ask is on my old boat, they always wore from the inside out. The fins on the impeller looked fine until you took it out, then it looked like it needed replacing. IMO, I would never run the boat over 200 deg, you are just asking for trouble. If your boat did not run this hot before, it shouldnt now.

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-12-2006, 8:19 PM

Byrd, I may take the impeller all the way out just to make sure. This is my first inboard boat and it was my first time out. So i dont know how it was before. It also was the first time the boat has been out this year.

(azwakekid) · (azwakekid) **Join Date: Apr 2005** 03-12-2006, 8:52 PM

just cause the impeller looks ok doesnt mean anything at all, the problem is that when the impeller sits over the winter the forms to the shape that it sits in, so its oval instead of round like it should me, idk it hard to explain, either way you should replace it...

(will5150) · (will5150) **Join Date: Oct 2002** 03-13-2006, 6:42 AM

220 is too high, unless you have a Fresh water coolig system. I'd change the oil and Trans fluid and see if that helps- check the thermostat too. 170 is the magic number.

(insuranceman) · (insuranceman) **Join Date: Jun 2005** 03-13-2006, 6:55 AM

My old 02 Outback with the 310 carb ran around 160-170. the new Supra SSV seems to be running around 175, but i think that is due to being new.

i would pull the impeller and check it out. call skidim and purchase a new one with gasket for around 30 buck.

(lzyboy) · (lzyboy) **Join Date: Jun 2001** 03-13-2006, 7:23 AM

Big E,

You can test your thermostat to see if thats the problem. Take it out, put it in a pan of water with a meat thermo... Turn it up towards HI as the water comes to a boil it should "pop" open - make sure it works & match the temp...

Lzy

(yosquire) · (yosquire) **Join Date: Jun 2005** 03-13-2006, 8:28 AM

I wouldn't expect power loss out of a Small Block Chevy until 235-240 degrees. The small block chevy engine is a sloppy beast – I mean, it’s late 1950’s technology. Though, the problem with power loss from an over heating condition is sever. It occurs when the moving metal parts have expanded so far they're rubbing into other parts. Then, they start shaving themselves down to fit their new crowded space.. That's where the power loss becomes permanent. Secondly, warping occurs when these metal parts dissipate their heat too fast.

You may have a faulty gage. And yes that is a suspect...Though, it'd be wise to assume it's not faulty and find the problem. One thing you can do is this. Get the boat running. When it hits 180 degrees open the engine hood and put your hand next to the radiator hose, or the intake manifold. If it's not hot, go a head and touch it. You should be able to hold your hand on 180 degrees for 3-4 seconds. Then, get it up to 220. Repeat the process -- except for the touching part, if you can't hold your hand near it. Then it is running 220. Also, splash some water on the metal when it's running 220. If it boils off, you know the temp gage is accurate. (water boils at 212 degrees)

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-13-2006, 1:34 PM

Thanks guys. I will keep you posted on the out come of this. I will pull the impeller out later on tonight. I have already ordered a new one.

(madchild1) · (madchild1) **Join Date: Mar 2005** 03-13-2006, 1:57 PM

mine ran 160 for about 100 hrs, then it went up to 170 and stayed. 220 is pretty damn high imho.

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 03-13-2006, 4:10 PM

OK, i pulled the impeller today and it doesnt have any blades broken and it is still soft but alittle deformed. I will be putting new one in but will a deformed impeller cause this?

Has anyone had this problem with a impeller that is not missing any blades?

(mobv) · (mobv) **Join Date: Jun 2002** 03-13-2006, 4:22 PM

As I said earlier - trash plugging the oil cooler. Same engine as your Mobius LSV - Intake goes through the V-drive then oil cooler then impeller. I added a strainer before the v-drive after the problem.

(snyper1d) · (snyper1d) **Join Date: Mar 2005** 03-13-2006, 4:25 PM

Also a couple of things to check:

1) Transmission oil cooler. Follow the raw water intake line from the thru hull fitting and the next stop should either be the raw water strainer or the trans oil cooler. If you see the trans oil cooler first in line, remove the hoses at both ends and flush the honeycomb coil with water/air.

The veins on the impeller might look alright but there is a chance that the hub could be spun. As others have suggested, replace the impeller at least once every other year if not every year.

(will5150) · (will5150) **Join Date: Oct 2002** 03-13-2006, 5:02 PM

Probably not the impeller- but they should be changed every 100-150 hrs anyway. I doubt that an 02 boat has only 48 hours on it- take it to the dealer and have them plug into the ECM- that's the most accurate measure. My boat's hour meter was off by over 100 hours ( total of 300)when I plugged it in and I believe the ECM, as I use the boat a lot. As stated earlier- change your fluids and check for material in the oil, in the bottom of the pan and check the temp guage as someone else suggested- that's probably your culprit as those sometimes go out and don't let water flow through the block. the temps your running are OK and aren't going to cause any issues- as long as they don't rise any further. good luck.

screws 03-14-2006, 8:32 AM

First check impeller, then check thermostat like Aaron said, then look for blockages.

(yosquire) · (yosquire) **Join Date: Jun 2005** 03-14-2006, 8:44 AM

Yes, I've had problems with impellers that were not missing any blades.

(paublo) · (paublo) **Join Date: Jul 2002** 03-15-2006, 9:05 AM

Just like everyone said, it should not go over 170. In a non-pressurized system, you will have steam at those temps. We have a houseboat engine/outdrive at Lake Powell that ran hot. The engine was ruined and replaced. The impeller was changed and all passageways checked. It ran fine and temp was ok at low rpms. Once it got over 2000 rpm it started to overheat again. After rechecking everything, including timing we couldn't find anything wrong. Finally someone told us to take off the exhaust manifold and check the water passages. We did and found that it was almost plugged. It passed enough water at low rpm, but with the restricted flow, it was not enough to take away the extra heat at cruising speed- thus overheating. You may have to carefully check the entire water path into and thru the engine. Anything could cause the problem. We think ours happened with owners running it in silty conditions with the low water level and that gets baked into the manifold.

To check the accuracy of the temp gage, buy a cheap contact thermometer and apply it to to different surfaces on the block. We found those surface temps to be very close to the indicated water temp.

Good luck.