75 GL1000 Running Hot???

[bronko37]

So I got this 75 GL1000 in early March. The gages on it were from a 78-79 model so there was no temp gage. I found a good gage set and installed it the other day. The gage still did not work. After a bit of reasearch I learned that it was probably the 7v regulator. So I harvested my 7v from my 76 to see if it would work. Viola! The gage started working!

Now for the issue. The bike seems to running hot. There is coolant and the fan does kick on. The bike does cool istself as well. However, it seems to be working in a temperature range that is too hot for my comfort. It's not even summer time yet. The bike is working in the very top end of the OK range and into the area between, hey thats ok and way too hot.

The bike is not getting into the white "overheating" area at all but I feel like it should begin cooling itself sooner than it does. Do these bikes tend to run hot? Is there a thermostate or switch that may need to be replaced? I have not begun any research yet, was just wondering if anyone had any tips to get started.

Thanks!

 

[slabghost]

Yes there is a thermostat that may need replaced or maybe the radiator just needs cleaned.Could be partly plugged inside or dirt between the fins. Are there bubbles evident in the coolant reservoir? It could also be the head gaskets are near gone. First things first. Use an external heat sensor and verify it actually is running hot. Lean carbs can cause the motor to run hot too. Is the air filter dirty?

 

[bronko37]

slabghost » Mon May 12, 2014 11:33 am[/url]":1qqur03k]
Yes there is a thermostat that may need replaced or maybe the radiator just needs cleaned.Could be partly plugged inside or dirt between the fins. Are there bubbles evident in the coolant reservoir? It could also be the head gaskets are near gone. First things first. Use an external heat sensor and verify it actually is running hot. Lean carbs can cause the motor to run hot too. Is the air filter dirty?

I have not flushed the radiator. I did not see any bubbles in the coolant resevoir, but I wasnt lookin for em either. Do you know the actual temperature range the bike should run in? There are not numbers on the gage just an operating range highlighted in white.

The air filter is clean and the carbs are good. PO had a Pistol Pete rebuild and the bike runs really well. Head gastkets are a concern for me. The bike smokes at start up with a white smoke. Not sure if its oil or not but the smoke stops after a minute. What type of coolant do you suggest in these aluminum motors? Was thinking it would be a good idea to just drain it and put some fresh in anyway since I have no idea how old the stuff in the bike actually is. Do you warm the bike slightly before draining?

I am trying to get this thing good before I take a trip on it with my dad over fathers day.

 

[joedrum]

hmmm could be head gasket leak tha continues till it cools off and is burning coolant off at start up ... but could be many other things .... a small leak would do something like this and clear up after running a bit ... be very watchfull here

 

[backlander]

Are the radiator air scoops installed on the bike ?

 

[bronko37]

backlander » Mon May 12, 2014 12:48 pm[/url]":2xmnfb3m]
Are the radiator air scoops installed on the bike ?

Yes they are on the bike. While we are talking about all the fluids my bike may be burning, is there any good way to check my oil level. I laugh to myself when I think abou the PO checking the oil when I was purchasing the bike. He got down on the ground and looked in the sight glass, you cant see nothin in that thing. I did a full oil change on the bike and you cant see anything in that glass empty or full. I dont know if the bike is burning oil or what but there is no way for me to check the stupid oil.....

By the way, the bike only smokes for about a minute upon start up. It does not smoke all the time when running.

 

[Joep]

If using dude stand smoking is normal... oil pools in the right side valve cover and gets sucked in to the combustion chamber. Also change the antifreeze to an approved for aluminum antifreeze.. clean the radiator.. when the bike first starts is the smoke odor sweet? .. that could be antifreeze.. just trying to jog possibilities here

 

[Ansimp]

If your thermo fan is cycling as per normal I am more inclined to think that there is a temp gauge wiring problem or sender issue. The gauge position is a reference to the resistance supplied by the temperature sensor so there are a few variables. On any vehicle I use the thermo fan switch to calibrate my expectations of the temp gauge. To work out if the thermo switch is right I look for overflow into the reservoir or use my infrared temp gauge if available.

 

[dan filipi]

Joep » Mon May 12, 2014 2:01 pm[/url]":340pmmso]
If using dude stand smoking is normal... oil pools in the right side valve cover and gets sucked in to the combustion chamber. Also change the antifreeze to an approved for aluminum antifreeze.. clean the radiator.. when the bike first starts is the smoke odor sweet? .. that could be antifreeze.. just trying to jog possibilities here

I think that should read
If using dude side stand smoking is normal... oil pools in the right left side valve cover and gets sucked in to the combustion chamber

What I find happens is while on the side stand, since it's a boxer engine oil can seep up past the rings into the combustion chamber while parked then smoke some on startup.
I purposely run the oil level on the low side to help reduce this.

 

[zman]

Start with the simple things first and change the fluid, any approved for aluminum will do, check the bottle they like to brag about it.I would do that first before you go any further.
If you can get a laser heat sensor, they are pretty inexpensive at harbor freight,25 -29 bucks then use a 20 percent off coupon and get a little off that, if not I have used a digital cooking thermometer but that was fixed inside the motor using clamps and fittings, maybe one can be used taped against the return radiator hose or in the fill tank ?
The thing you want to know first before you take anything apart is if it is truly running hotor is it a gauge reading high.
Good luck, hope it is an easy one.

 

[slabghost]

A little smoking (white) at start up can be condensation. If it smells sweet though I think it's time to order head gaskets.

 

[bronko37]

Thanks for all the info guys. The smoke does not smell sweet. I think i need a replace on the head gaskets. Which i will do when i change the valve guide seals. I think that is most of my issue. As far as the temp goes. I may have located my gremlin. While working on my 76 i realized there was a section of hose hanging from the overflow lid down into the over flow coolant. On the 75, no hose. I put a section of hose on and rode the bike this evening about 40 miles with my wife, what a great night for a ride. The bike stayed in the normal range. It was still to the upper end of normal but never got to the uh oh range.

I will get a laser thermometer and check the actual engine temp. Suggestions on where to shoot the laser? On the manifolds or what? Let me know. I'll keep you posted.


I a,getting ready to tear this bike down for new tires and a back end rebuild to prep it for a longish trip. Gonna be riding the 76 for awhile. I just got it running well. Still needs points and timing set but its plenty rideable.

 

[slabghost]

I'd check the temp at the coolant fitting on top of the head or where it meets in the middle. Preferably when the fan starts and stops just so you know.

 

[Ansimp]

dan filipi » Tue May 13, 2014 8:44 am[/url]":2sp8iksa]

Joep » Mon May 12, 2014 2:01 pm[/url]":2sp8iksa]
If using dude stand smoking is normal... oil pools in the right side valve cover and gets sucked in to the combustion chamber. Also change the antifreeze to an approved for aluminum antifreeze.. clean the radiator.. when the bike first starts is the smoke odor sweet? .. that could be antifreeze.. just trying to jog possibilities here

I think that should read
If using dude side stand smoking is normal... oil pools in the right left side valve cover and gets sucked in to the combustion chamber

What I find happens is while on the side stand, since it's a boxer engine oil can seep up past the rings into the combustion chamber while parked then smoke some on startup.
I purposely run the oil level on the low side to help reduce this.

Somewhere in my research the other day I ended up on a site where the owner made a manual dip stick for his oil level that was inserted through the oil filler plug towards the front of the motor ( slips past some gears etc) and ground a mark in the piece of wire to correspond with his full mark. When checking for his correct oil level he measured in the correct volume of oil and said that that corresponded with the center of the site glass ( where the wiper mounts). He also stated in his experience when he filled the sump to the top level in the inspection window his bike always seemed to use some oil and he would top up when it reached halfway. Once he started filling the sump to the middle position he no longer seemed to use oil. This may be the reason that when on the side stand the oil can seep up and be consumed when filled to the top mark.

 

[Joep]

No that should have read using the side stand.. :head bang: :head bang: ...my android phone loves to do swypos... as I use Swype keyboard :laptop: :laptop: ... sorry folks.. if there was any confusion :whistling: :whistling:

 

[Steve83]

At what point on the temp gauge does the fan come on? It should be at 1/2 to 3/4 mark. After it comes on, does it eventually shut itself off, or keep running? The fan switch is in the upper radiator hose outlet, at the front of the engine, which also houses the coolant thermostat. Check the thermostat as well - if it's not openoing properly, she'll overheat.

 

[bronko37]

Joep » Mon May 12, 2014 11:11 pm[/url]":lrjq64rd]
No that should have read using the side stand.. :head bang: :head bang: ...my android phone loves to do swypos... as I use Swype keyboard :laptop: :laptop: ... sorry folks.. if there was any confusion :whistling: :whistling:

I liked it better as "the dude stand". I think thats what i will call it from now on. Got the center stand for long term and the dude stand for short stops. :music:

 

[bronko37]

Steve83 » Mon May 12, 2014 11:31 pm[/url]":25hxb470]
At what point on the temp gauge does the fan come on? It should be at 1/2 to 3/4 mark. After it comes on, does it eventually shut itself off, or keep running? The fan switch is in the upper radiator hose outlet, at the front of the engine, which also houses the coolant thermostat. Check the thermostat as well - if it's not openoing properly, she'll overheat.

The fan kicks on at around the 3/4+ area. It runs awhile and shuts off. Everything seems to be cycling as it should. Im gonna check the actual temp of the bike to see what it is really running.

 

[mcgovern61]

I liked the "dude stand" too! I thought it was very creative! :smilie_happy: :wave:

 

[Joep]

Credit belongs to my phone... thanks guys..