Water pump/front cover refresh

[mwbill37841]

a big amen to that

 

[AApple]

Otay! I was able to remove the t-stat housing without having to loosen or do anything with the carbs. :yahoo: I had to remove the engine shroud to get to the rear bolt, but that was all. Unfortunately...I dint have a long 8mm wrench, so I had to make do with a tiny(4" long) 5/16" wrench. Once the rear bolt was loose, I was able to get one finger of one hand on it, and used a long screwdriver in between the two carbs on the left side, to spin the bolt all the way loose. Lucky for me, all three of the bolts came out with no resistance once they were broken loose. :heat:

tstat2

• AApple
• Jul 10, 2012

Broken bolt in housing....dammit....

tstat3

• AApple
• Jul 10, 2012

You CAN remove the thermostat housing without removing, or taking the carbs loose.

Since I have time before my new wp and housing get here, I wanted to see if I could come up with some sort of seal to go between the fan shroud, and the top of the radiator. There is a HUGE gap there, where air can go right between the shroud and the radiator, instead of going thru the fan shroud, when the fan is running. I wanted to find a way to make that air go thru the fan and shroud, instead of the fan basically just pushing that air up/over the top tank of the rad. I think this will work. I will also use some foam rubber sealing(weatherstrip) around the entire perimeter of the shroud, to make sure that when the fan is running, it is pulling as much air thru the rad as possible.
The blue foam you see is "U" shaped, and I did have to trim some of the height off of the part on the inside of the shroud, so the fan blades would not hit it.
Whaddya think? :ahem:

tstat4

• AApple
• Jul 10, 2012

I'm trying to find a way to better seal the fan shroud to the radiator. There is a LARGE gap...

tstat5

• AApple
• Jul 10, 2012

Seal on shroud.

 

[dan filipi]

Good idea me thinks.

 

[scdmarx]

That's a great idea!

 

[AApple]

Well...if you've ever had the rad/fan off of one, you'll know exactly what I mean by the large gap up there. Just don't seem like it would be very efficient the way it is, to me. Too bad they couldn't design the dang thing to where the fan was lower on the rad, so it would pull more air thru the actual fins...
Imma gunna give it a shot, anyway. Can't see what it would hurt. :whistling:

 

[mcgovern61]

Interesting idea! I do not think the gap is actually an issue. The blade tips of the fan are inside of my shroud and do not protude forward in to that open area. Remember that the fan is pulling air through and not pushing. The fan blades are creating the pressure differential on the backside of the blade hence creating the vacuum that is pulling the air through in the first place. The greatest pressure is on the leading edge of the back of the blade which is within the shroud so the open space between the shroud and the radiator actually feeds air to the fan from areas not withing the diameter of the shroud (although not very efficiently).

Also, the fan is at the top of the radiator where the hottest coolant is entering the radiator. I do not agree that this was the most efficient design by Honda, but I think I understand the engineering.

 

[AApple]

Good points, Gerry. I realize this may not help much, but I think it will help some. I see it as a vacuum leak of sorts...The fan is drawing in air from around the radiator...not thru it. The open gap, while not really obscenely large, is still an area of less restriction than the radiator, so the fan will pull air thru that opening. Closing it will allow the fan to draw more useful air thru the rad. I seriously doubt I will see any drastic reduction in operating temperature, but it might help a little in the stop/go traffic I am stuck with. Either way, I'm sure it won't hurt anything, and besides...it's the only thing that ain't costing me any $$$$ on this thing lately! :smilie_happy: :smilie_happy: :smilie_happy:

 

[mcgovern61]

Either way, I'm sure it won't hurt anything, and besides...it's the only thing that ain't costing me any $$$$ on this thing lately! :smilie_happy: :smilie_happy: :smilie_happy:

:smilie_happy: Amen to cheap repairs or corrections! :smilie_happy:

It appears that the system was designed with the bike moving air via the air dams and it also appears the fan shroud positioning was not given much thought at the time. My buddy with the GL1800 said that Honda had a terrible time with (having a brain fart) 1500 or 1800 fans blowing forward to prevent the rider from getting all of the heat but there were times when the blowing forward was not enough and the engines overheated. The newer GL1800's all push air out sideways now with two heat exchangers on the sides. Point is, Honda has had struggles with these cooling system designs.

 

[mwbill37841]

ok,if i'm reading this right the fan should be drawing air through the radiater not blowing right?

 

[joedrum]

yes

 

[mwbill37841]

ok. i had to reverse my fan wires but she is still running hot but not boiling over,new coolent,drianed and refilled. is the water pump be hind that same pice wher i drianed the coolet?

 

[AApple]

Yup. It can only be removed/replaced by removing the front cover from the engine. There are 3 bolts on the backside of the cover that hold the waterpump in.

gwwp4

• AApple
• Jul 8, 2012

Front of cover w//water pump.

I got my new t-stat housing today, so I went ahead and installed it, along with the coolant crossover tube for the left side. I fought with getting the dang head end on so long I decided I would stop once I got it on, and finish the other side tomorrow evening. The new waterpump should be here tomorrow, too.

006

• AApple
• Jul 11, 2012

"New" thermostat housing..withOUT a twisted off bolt in it!

I also drilled a few holes in the edge of the t-stat. Some t-stats have a small hole, with a little rod/orifice in them, to help bleed the air out of the system. I want to do that, along with making sure there is circulation all the time. :good:

005

• AApple
• Jul 11, 2012

I drilled several 1/8" holes in the outer edge of the t-stat.

 

[danf]

Joel good luck to you sir..

 

[AApple]

New water pump arrived today... :Egyptian:
I got it installed in the front cover, then finished installing the right side coolant crossover tube. It went in a little easier than the left side did. Also got the radiator painted. I took it to the shop and ran it thru the washer, to get all of the oil residue out of it, and just clean it up some. It is now painted, and ready to install. I still need to install the rear shroud, and thermostat, the front cover w/water pump, and then install the timing belts. I'm hoping I can get this thing running again this weekend, as long as I don't screw something else up. oh2:

New pump.

glwp2

• AApple
• Jul 12, 2012

Jen-you-wine Honda Water pump.

glwp 003

• AApple
• Jul 12, 2012

New pump

Front cover ready to install.

glwp4

• AApple
• Jul 12, 2012

Cleaned/painted front engine cover.

Weep hole locations.

glwp5

• AApple
• Jul 12, 2012

Location of "weep" holes in pump and front cover. This is where oil/coolant will leak out of if...

And just in case you're curious...here's the old water pump, disassembled. :builder:

glwp1

• AApple
• Jul 12, 2012

Water pump innards. Left to right:
Impeller-ceramic seal(2 pieces)-snap ring-front...

 

[joedrum]

looks good joel but not as good as if it was on the bike and running ...this has been a looooonngggg pit stop .....but near as long as some of the projects that i get into :mrgreen:

 

[danf]

I would sy he is set, new water pump, new stator, I say it's road trip time..

 

[mwbill37841]

ok i haven't got to check the water pump yet but i'm betting it's bad. so where do i find a water pump and if anyone don't care to say how mutch?
thanks bill :headscratch:

 

[AApple]

Here's where I got mine...$123 + $8 shipping. Total to my door was $131 & change.

click for link

 

[dan filipi]

Hang on to the old pump, I believe they can be rebuilt. Maybe could sell it and recoup some costs.

 

[mwbill37841]

ok thanks,now i got to save up my pennies. so i can get one.