'92 70hp is still getting hot.

[wlbolerdo]

I gave up and called a mobile mechanic who twice now has not shown up. He did mention pulling the gear case down and attaching a water hose to the water tube and checking for a blockage as a starting point. Does anyone know what I be looking for? Would I be running the motor or not? Would the t-stat be out with the cover off?
T-stat and impeller are new. Seems to be a good stream with the motor in a tank. Could the heat problem come from timing and/or air/fuel settings off?
Wayne

 

[david_r]

Re: '92 70hp is still getting hot.

your therms are at the base of the engine in the rear......to get to the oumop youll have to remove the lower unit.



did you replace the whole pump or just the impeller?
the housing may be bad


you may have a piece of the old impeller stuck inside the motor somewhere. you could remove the lower unit and do the water or compreswsed air test yourself.........its simple. or you could have bad therms..........im an auto mechanic and believe me just because its brand new doesnt mean its good.................it could have been made on a monday morning or a friday afternoon when peoples minds are elsewhere

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

I replaced the entire pump assembly and checked the t-stat in hot water, it opens and closes just fine.

 

[lyncraft_mechanic]

Re: '92 70hp is still getting hot.

If you don't mind me asking, how do you know the engine is overheating?

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

I'm using the gauge on the dash which at idle in a tank was reading about 150 degrees. On the muffs it gets to 160. Last time out it went to 220 and I brought it right back. That time you couldn't keep your hand on the flywheel. On the muffs the exhaust housing gets extremely hot at idle.
It's got to be something stupid but I can't figure it out.
Wayne

 

[luisdiaz]

Re: '92 70hp is still getting hot.

It's got to be something stupid but I can't figure it out.
Wayne

Did you verify the gas/oil ratio?
Is it over revs? (Rpms in idle are normal?)

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

I do a 50:1 mix(I mix it myself in the fuel tank). It has a new tank of fuel.
RPM's are about 1100 in neutral. I would think that in gear it would drop to 600-800.
Wayne

 

[luisdiaz]

Re: '92 70hp is still getting hot.

I'm using the gauge on the dash which at idle in a tank was reading about 150 degrees. On the muffs it gets to 160. Last time out it went to 220 and I brought it right back. That time you couldn't keep your hand on the flywheel. On the muffs the exhaust housing gets extremely hot at idle.
It's got to be something stupid but I can't figure it out.
Wayne

By far the best way to get temp reading is with an infrared thermometer. You can get one at your nearest Pep Boys. http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93984 here you will get it cheaper but will have to wait. It does not make any sense to me that she is getting so hot if you are at that revs, has the oil/gas ratio fine and has a nice water steam.
When you replace the impeller, was it missing a piece? Like David R said you may have a piece of the old impeller blocking a section of the cooling path.
My opinion (and am not an expert, just the happy owner of a J70) is that at this point you should not be concerned about timing or air fuel mix. And I conclude that because the revs.
Have fun

 

[mikesea]

Re: '92 70hp is still getting hot.

You have a single thermostat at top of engine.If you are the one that tested it ,Im sure you know where it is located.You might want to remove the thermo and do a test run to be sure it is the thermo that is bad,It wont hurt anything .Possibilities are,as said a broken piece of impeller could have found its way and is blocking the flow.Has the engine been run flushing with fresh water after use.If not,you may have corrosion and/or sand build up in the passages.You Can try removing the lowerunit,and thermo.Try back flushing thru the thermo opening with a garden hose and rag to help with splatter,you may be lucky.If you are sure impeller job is good,start the eng on muffs ,thermo out and open and check flowout the thermo also possible flushing.If none of that helps,I would take head off and check for any deposits within the waterpassages in head and block.Next would be the exhust cover on the portside of eng.On the 3cylinder engines sometimes the waterpassages in those areas get plugged.There is a possibility of blockage where the powerhead and midsection meet ,the water tube can get something like impeller blade caught there,if you have access to compressed air you can blow thru the thermo stat like described with water ,

 

[Mas]

Re: '92 70hp is still getting hot.

Just an idea...and certainly I'm not an authority...what about the chance of running too lean on a cylinder or two??

Too lean equals no lube equals friction .

Just a thought,

MAS

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

Here's alittle of what I've done:
Replaced impeller assemble.
Replaced water tube grommet(had to pull power head to get to it)
Cleaned and blew out exhaust adapter-found no obstructions. I did break off three bolts in it to the tune of $55.00 to remove them.
Have had both exhaust cover and head off to blow it out while power head was off the boat. I have not tried to back flush the motor with water but I will certainly tomorrow if possible.
I'll post what I found by Friday. I'm always open to suggestions.
Wayne

 

[56 rude]

Re: '92 70hp is still getting hot.

Here's alittle of what I've done:
Replaced impeller assemble.
Replaced water tube grommet(had to pull power head to get to it)
Cleaned and blew out exhaust adapter-found no obstructions. I did break off three bolts in it to the tune of $55.00 to remove them.
Have had both exhaust cover and head off to blow it out while power head was off the boat. I have not tried to back flush the motor with water but I will certainly tomorrow if possible.
I'll post what I found by Friday. I'm always open to suggestions.
Wayne

It is entirely possible that your waterpump housing is not sealing properly and your not getting the proper water flow.I worked on a 33 evinrude this summer that drove me nuts because it refused to pump water properly not matter what i did.So after a a lot of head scratching i decided to try one last thing before blowing it up with a nuke,i liberally coated the base of the pumphousing with a good avaition sealer and reassembled for the tenth time .Presto! pumps water like a champ and took me on a 70 plus mile river trip with nary a peep!Hope this might help as i know how frustrating it can be when everything seems right but isnt.

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

Here's what I did Friday:
Dropped the lower unit and attached a garden hose to the water tube, removed t-stat and cover then flushed the motor. Stuck the hose against the t-stat grommet and back flushed, had plenty of water in both directions.
Saturday I bought an IR thermometer. I ran the boat on muffs with and without the t-stat. Without the t-stat in it didn't seem like it was getting enough water, not a constant steady stream of water at the peehole! I took the muffs off and filled up my test tank, now the water is peeing out great-this tells me my waterpump is working? Thermo readings are all below 160. I took it out in the canal with the t-stat in and ran it pretty hard. Temps at the exhaust cover were around 120-130 as well as at the top of the motor! The opposite side of the motor on the block at the bottom cylinder was around 196 while the top was around 130.
Does anyone have any ideas?
Wayne

 

[mikesea]

Re: '92 70hp is still getting hot.

i THINK YOU HAVE SOME BLOCKAGE EITHER IN THE EXHUST PLATE WATERPASSAGES OR HEAD AREA

 

[wlbolerdo]

Re: '92 70hp is still getting hot.

When you say exhaust plate are you talking about the exhaust adapter that the power head sits on? I've had that off to replace the water tube grommet and it was clear and I cleaned it up anyway. Now I'm going out to take the head off and check the water jacket around the cylinders. I'm also going to hook up the muffs and see what happens with the head off.
I'm pretty much doing what you suggested but I'm getting tired of pulling stuff apart to find nothing. I do appreciate your help!
I'll post what I find in a bit.
Wayne

 

[mikesea]

Re: '92 70hp is still getting hot.

on the portside of your powerhead,you will see a large triangular shaped plate,that covers your exhust ports and has water passages that pass whithin,you might find some salt,sand,impeller ,corrosion blocking some passages,I believe they are3/8 head screws and plenty of them,your ground may also be attached,watch for stuck bolts,but if your pulling the head anyway,check the block and head water passages first,you may find your problem there saving you work,keep tn touch

 

[ezeke]

Re: '92 70hp is still getting hot.

Your engine is one of a series that had circulation problems caused by the placement of the tell-tale. It was well covered in SB 2276 R1 but your motor may not have been changed.

Click the thumbnail for the service bulletin.

 

[arkansascountry]

Re: '92 70hp is still getting hot.

My outboard has a warning buzzer or horn on it that beeps when it is hot. There is a small hose that sticks out of the engine cover that shoots out water--does it do this- if not than you need to run a wire into the block through the hose or disconnect it and see if mud or objects has stopped it up, this allows the water to flow through the engine and keep it cool. By the way you do have the foot of the motor in water--correct---There is ears or suction cups that are made to place on the foot with a water hose.

It could also have a blown head gasket also, tighten the head bolts or check the head gasket. It pumps water from the bottom through the engine out the hose mentioned above.

 

[mikesea]

Re: '92 70hp is still getting hot.

ezeke has a trick or service bullitian I never heard of.In this case with the differential of heat ,may be the answer.Hope it works.Will save a few bucks,lots of swear words too

 

[david_r]

Re: '92 70hp is still getting hot.

i beleive the bulletin is in the faqs but if its not here it is


http://forums.iboats.com/showthread.php?t=222677&highlight=pee+hole+tell+tale