coolant temperature sensor

[admin]

You don't need to apologize, all the private discussions here are out in the open. :lol:

[silverbull]

Don`t have the tie to get here often, but when I do, I`m quite active, as you might have noticed And no, I know, after been reprimended.. All should be so everybody can involve. Thats the main thing at htis forum, right? 8) :lol:

[admin]

That's it, you got it right.

[SIR tricky]

My 1200 fan never came on until I did the alternator conversion. Now it comes on often. I guess I need to look at sealing the shroud to be sure I am getting max air flow through the rad and not around it. It has'nt boiled over yet and I certainly dont want that to happen, especially since I ride with an air cooled HD most of the time.

That was the same with me, I hardly ever had the fan come on, only in extreme hot weather and traffic hold ups.

When the coolant boiled over while measuring 3 bars it got me wondering. now that the sensor has been changed it reads correctly, telling me that the engine is getting hot and eventually the fan kicks in, but there lies the rub, it never got this hot before the external alternator was installed.
I have stripped it down, checked the water pump, there doesnt seem to be a problem there, I am re-installing it with new O rings.
Its all well and good installing a more efficient fan, but what is the reason for the engine running hotter?
The inner shroud has been vastly altered, is this the reason for the hotter engine?
We shall see.

[admin]

Did you happen to take any pictures of your fan/shroud assembly while you had it out? It would be interesting to see your mods.

Here's a pic of mine showing how I cut 1 inch off each blade then built a pseudo ducted fan unit out of the original shroud. It works pretty good. You'll also note how I added the oblong tabs where the rad mounts to raise the entire assembly up 1 inch.

My next step is to trim another blade so that minimal air can leak between the blade and the shroud to render maximum air flow to help out on the super hot days in slow moving traffic.

[T. Bix]

Doesnt the OEM fan push from rear of the rad to the front?
I am sure that when the fan comes on I can feel the air from the fan at the front of the rad.
However that doesnt do anything for the fact that I think the engine is getting hotter than it was last year.

Tricky, I am new here and don't really have a feel yet for folks personalities or senses of humor so I'm not sure if this is a serious question or not?????? but here goes ...... the fan should draw air from the front to the back and push it through where your carbs are. This is possibly a factor (check the wiring from when your alternator was installed)...... also remember a temp indicator is really just a volt guage with an arbritrary scale to represent whatever temperature the manufacturer decided it should show you ........ meaning if your new charging system is putting out higher, lower, or more consistent voltage it will change what you are used to seeing as an indication, It may have been giving you a false sense of security before and been constantly on the verge of boiling over!!

good luck.
tim

[SIR tricky]

Any question made that gives my old brain a kickstart to look for other solutions is serious believe me. I shall check on the wiring.

Agreed on the fan direction however looking behind the fan there is no way air could ever be directed over the carbs as there is a steel bulkhead between the fan and the carbs.

There are also inner shrouds which also deflect the the hot air to the side where the air is dispersed through the side shark gills when driving, which could be forced under the radiator to the front when in the parked position with the fan running as there is no forward motion to disperse the hot air 100% to the shark gills, you can feel the hot air directed there, that was what I was feeling.

During the alternator instalation, the inner shroud is altered to make way for the alternator, is this the factor in the overheating?

The coolant sensor was tested and found giving reading lower than were acceptable according to the Honda workshop manual.
It was tested in oil heated to the temperatures indicated and showed lower ohm readings that were suggested, giving me the impression that the engine was actually cooler than it actually was.
looking here:

You will see that the sensor on the aspencade models shows a 2 pin contact.
This sensor is no longer available, the only one available is the single contact version that was installed on the Interstate models.
shown here:


The only difference (I hope) is that the body on the single contact is the ground whereas the body on the double contact sensor is isolated from both contacts and one of the contacts was ground and hopefully the sensor ohm readings at the various temperatures are correct. I could have of course tested the new sensor to verify but one does hope that the expensive parts that Honda supplies are the correct ones.
There also had to be a modification to the sub harness to accommodate the single round contact rather than the two spade original.

As far as voltage changes with the new alternator, I didn't change the alternator because the internal one had died, it was giving me a comfortable 13.9 volts last year. The external shows fairly well the same except after riding a score or more miles the voltage reads 14.1
I wanted the extra voltage that it was capable of delivering to power spot lights and other lights without fear of discharging the battery.

I can go back to the original alternator to see if the removal of the external alternator does have any bearing on the overheating.

But I shall try other routes first.

[admin]

Tricky, I doubt if the removal of that section of plastic is responsible for your overheating condition but if it concerns you go to a plastics shops and buy a sheet of heat formable plastic and use a heat gun to configure a new piece that will seal the area and allow room for the alternator.

[T. Bix]

Yeah I know about the bulkhead but I was thinking more like they designed it in a way to maximize rider discomfort level when sitting in traffic with the fan running (blowing aft right onto the rider's legs)...... I just couldn't come up with a way to say that last night.... :lol:

[admin]

I'm thinking that the bulkhead is more there to prevent the gasoline from boiling in the carbs.

[T. Bix]

Tricky, did you get a handle on your cooling problem? It's been a while and the weather's getting warmer.... I was just wondering. Let us know

[SIR tricky]

This is a follow up on the coolant sensor for the 1985 GL1200 Aspencade model other Aspencade 1200 years may be the same, I can't verify them but I think they are.

After fruitless searches on the Net and at the local Honda dealer for the correct coolant sensor I decided to write a letter to Honda Canada customer service to see if they could supply me with the correct part or even the correct part number.

All the parts fiches available on the net are the same, they do not show the correct part number for the Aspencade coolant sensor, they show the Interstate sensor for the Aspencade sensor which will not fit the existing wiring harness.

If you read the posts prior to this you will see how the part is different.

After a call from them even they cannot locate the correct part (boy are we in trouble) they obviously use the same parts fiche.
They recognize that there is a difference but after a fruitless search they cannot come up with the part or number.

Their only suggestion is for me to take the bike to the dealer (who also cant find the part) and have them (dealer) talk to Honda about the problem.

I think I posted previously that I have used the available Interstate sensor and modified the sub-harness to fit.

I do think the correct sensor should be available. They did make the statement that "they hadn't had any other queries about the Aspencade sensor being unavailable although they do accept that there is a difference.

[SIR tricky]

Follow up on the over heating:OCT 20

I think I finally got a handle on my overheating problem.

It seems that I had a very slight head gasket leak that allowed coolant to pool into one cylinder after the engine was shut off. We could smell the coolant in the exhaust on startup.

While the engine was running it pushed exhaust gases into the coolant thereby raising the temperature of the coolant.

I replaced both head gaskets along with a few other O rings and gaskets.
I reworked the sub-harness in order to utilize the Interstate single pin sensor also replaced the plug on the fan switch with crimped on female bull nose connectors.

although I havnt had the bike out on the road yet it certainly seems to act like it used to while running in the garage.

I ran the engine to operating temperature (4 bars) it took a lot longer to reach that temperature than it has in the past year. I allowed it to rise up to 7 bars, the fan kicked in and after a few minutes the temperature dropped back to six bars.

What it had been doing while in the same conditions (running in the garage) it would run up to 7 bars, the fan would kick in and the temperature would keep climbing untill it reached maximum, I think that that having the Evans coolant in it this year allowed me to operate the bike without it boiling over.
I am running regular 50/50 coolant in the bike again to see if the problem recreates itself, somehow after changing the head gaskets I dont think so.

Although it is a cooler time of the year I shall take the bike out when I can.

There was very little visible evidence of a coolant leak when I took the heads off but I think it was the left head that was leaking.

There was no oil in the coolant and no coolant in the oil so I think the leak was confined to a very tiny leak in to the water jacket.

_________________

[admin]

I'm glad you finally got that sorted out Tricky. Sometimes those kinds of problems can have you pulling your hair out.