Over heats at every light

[stevebritt]

I just purchased my 1984 Venture 1200, its a great bike but at every light I sit at the sucker gets in the red. I replaced the cap and still over heats sitting at idle. What do I do?

[bongobobny]

Ummmm, there is a chance that the bike isn't really overheating!! A known issue with the MK1 ('85 - '85) temperature gauge is that it reads high! Is the fan kicking on at all??

 

Maybe the cooling system needs flushing. And yes, even in Florida you should use anti freeze, not necessarily to protect from freezing, but the anti freeze coolant mixture will tend to prevent overheating as well. The stuff sort of resists boiling much better than water does. Make sure you use coolant compatible with aluminum.

 

Also, there is a product out there called "Wetter Water" that enhances the cooling system's ability to cool.

 

Getting back to the fan, if you let it idle after it warms up, it SHOULD kick on after several minutes in hotter temperatures such as in Florida. There are several ways of testing the fan. One of the most effective tests is to locate the thermo switch and jumper a ground to the Blue/Green wire, this should automatically turn the fan on even without the bike actually running, just the ignition turned on. If it doesn't, you either have a bad relay, a bad fan motor, or a wiring problem. If the fan kicks on, but neve4r kicks on no matter how hot the engine gets, then the thermo switch itself is bad, or it has lost it's "Ground at the black wire. A quick continuity check to ground should verify if the ground is indeed at the black wire. Also, there used to be some aftermarket switches on Ebay that operated (turned on) at a lower temperature...

[cowpuc]

Got some mighty healthy advice from my good friend Bongo there Britt.. Might add that the early Ventures had a problematic plastic water pump impeller. I have swapped out a couple of them that had gotten so fragmented that they circulated very little coolant.. May just need to change it out. Not a bad job but very important and one that if the bike were mine and I could not verify thru the previous owner that it had been done I would take a peek at it. In the process of doing so I would also swap in the new seals for the impellar shaft..

You also may find when you open the water pump up you have a bunch of goo built up in the water pump cavity. If so, dont be fooled into thinking all is good just by cleaning it up. If she's still got the plastic impellar, swap it out even if it appears ok - those plastic pumps are a disaster waiting for road gremlins to gather at the most inopportune time..

Edited May 14, 2016 by cowpuc
misspelled "but" with "by",, brain to finger wiring needs reprogramming

[Flyinfool]

As Bob said, it is normal for the 83-85 to read in the red at stops, and close to the red all the time. Its just the way they calibrated the gauge. As long as the fan is cycling on and off while stopped, you are good.

[bongobobny]

Oops, forgot to tell you where your thermo switch is! It is located on the right side of the bike close to the top and near the radiator, mounted on a T unit which is part of the radiator hose. I can't remember if you can see it or not with just the engine side cover removed or whether you have to take the right upper fairing off as well...

 

There IS a downloadable Factory Service Manual in the First Generation Read Only Technical Library!

 

http://labs.trunkful.com/vrmanuals/8385servicemanual.pdf

[bongobobny]

Got some mighty healthy advice from my good friend Bongo there Britt.. Might add that the early Ventures had a problematic plastic water pump impeller. I have swapped out a couple of them that had gotten so fragmented that they circulated very little coolant.. May just need to change it out. Not a bad job but very important and one that if the bike were mine and I could not verify thru the previous owner that it had been done I would take a peek at it. In the process of doing so I would also swap in the new seals for the impellar shaft..

You also may find when you open the water pump up you have a bunch of goo built up in the water pump cavity. If so, dont be fooled into thinking all is good just by cleaning it up. If she's still got the plastic impellar, swap it out even if it appears ok - those plastic pumps are a disaster waiting for road gremlins to gather at the most inopportune time..

Yup!! Good point Puc, after I posted I remembered that as well!!

[cowpuc]

also may want to check the coolant bypass valve down below the rad and make sure it is in the correct position.. Its a small black valve Teed into the coolant lines,,,,,,,, located above the oil filter housing,... Need a picture?

[cowpuc]

Hey Bongo,,, got another one we both forgot!!

 

Hey Britt - me and that varmint BongoBob would like to you to VentureRider!!!

[cowpuc]

Oops, forgot to tell you where your thermo switch is! It is located on the right side of the bike close to the top and near the radiator, mounted on a T unit which is part of the radiator hose. I can't remember if you can see it or not with just the engine side cover removed or whether you have to take the right upper fairing off as well...

 

There IS a downloadable Factory Service Manual in the First Generation Read Only Technical Library!

 

http://labs.trunkful.com/vrmanuals/8385servicemanual.pdf

 

 

,,,,,,,,, I snapped a picture of that switch for another member a while back and posted it... Might be able to find it with a search here - will check it out... Hey Bob,, most of the times I have had problems with that sending unit it has been a loose connection resulting in the gauge reading nothing (needle reading no temp).. If the device actually fails is it possible for it to fail with the result being a "high" reading?

Britt,, dont let ANY of my questioning Bongo here be misleading.. Picture yourself having just walked into an Electronics 101 classroom with yours truly leaned back in a students desk and Professor Bongo standing at the chalkboard covered in dust and at me wondering why he ever took the teaching job ..

Oh,, by the way,,,, signing up for the actual classroom is only a buck a month - well worth it,,,,,,,,,,,,, especially if you enjoy giving college professors a hard time:crackup::crackup:

[DblTrbl]

Don't know much about 1st Gens and I'm learning about 2nd gens as I go. However to me, it sounds like you may have some Harley parts on your bike....

[bongobobny]

OK in chat last night we came up with a couple more possibilities! First, from Cowpuc, are you sure you are running on all 4 cylinders?? These bikes actually run surprisingly well on just 3 cylinders, and being you just got the bike, it may have been running on only 3 cylinders. Best way to check is when the bike is cold start it up and carefully check each exhaust for equal heating up. If you want to do it more professional get a heat sensor and look for equal temperatures. That would make the bike run hotter in general because it has to work harder.

 

A second possibility is you probably need to sync all 4 carburetors to each other. This is done with either 4 vacuum gauges or a device called a Morgan Carb Tune which is 4 vacuum monitoring devices all bundled into one neat hand held device. Unbalanced carburetors also make the engine work harder thus increasing the running temperature.

 

Now remember, when at a stop, your engine temperature WILL rise a few degrees or so because there is no airflow through the radiator. That's the main reason for the electric fan, to pull air through for cooling when there is no air being forced through.

 

Now to Puc's observation! There are TWO sensors on that tee, one is a variable output that drives the gauge to read equivalent temperature, and the other is a fixed on or off to turn the fan on of off. Yes, if the wire comes disconnected for the variable one the circuit for the meter is disconnected and the meter reads zero because there is no current running through it. Yes, it is easy to accidentally knock off that wire while doing something else in the area, and many of us have done it!! With the fan switch sensor, if either the output wire to the fan relay comes disconnected, or it looses ground, the fan simply will never turn on!

 

Oh yes, the most important part that Puc brought out WELCOME TO VENTURERIDER!!!

[bongobobny]

PS to Dennis (Double Trouble) the most important thing to learn about 1st gen's is they are faster and handle LOTS better than a 2nd gen, but they are not as comfortable...