Water pump Diagnose/Replace - Help

I hope you guys are more helpful. The other forums I'm on don't really want to help because I have a "special case" and not quite stock anymore.

Anyway, my problem is the old I'm overheating issue. The water has to travel twice the distance than a normal VFR, so I'm starting to suspect the water pump. Both the inlet and outlet line from the radiator run right next to my shifter, so I can easily feel the heat going in and out of the radiator. Usually, while driving I can grab the inlet line which is hot, and the outlet line, which is less hot, and I know that water is flowing and all is good.

But now, Its been getting up to 250-260F very quickly, and both lines to the radiator feel cold. Before throwing parts on it, What's a good way to determine for sure that the water pump is bad? I was going to just pull the hose off of the outlet of the water pump while running and see if it pushes water out, but I thought there had to be a better way.

Also, if it is bad, where's a good place to get another one? Or anyone got a spare? (I got parts to trade!)

To get a better idea of what Im working on, Google "VFR Reverse Tryk" and mine is the first one, the facebook page. Or see link in my sig.

 

Sounds a bit more like a thermostat to me. And pics of project please.

 

Hmm, whats a good way to test that?

And if you click the link in my sig, you will get hundreds of pics.

 

Another possibility is a blockage in the line somewhere. ..

 

Glad you got it to all come together, Viper.

What was your motivation behind doing something like this? Just because? Are you/significant other handicapped? (No offense meant, as my wife is handicapped). What's the overall weight on that thing?

I don't posess anywhere near the skill or mechanical ability that you and others might have, but is the rad maybe a bit too small (generally speaking - and not necessarily related to your overheating problem). Is the stock water pump "beefy" enough to move all the coolant, since you mentioned its running about twice as far as a standard VFR?

Inquiring minds want to know. Or just annoy you.

 

TNRabbit, I have checked for blockage outside of the engine, and found none. I did this by hooking up a hose to the outlet of the thermostat and pushing all the water through till it was clear. I did not check for block between pump and thermostat. I believe I will need to tear into the engine to do that, unless you know of a better way.

Pliskin, Replay is in line below.

Glad you got it to all come together, Viper.

What was your motivation behind doing something like this? Just because? Yes, just because. I have flipped many bikes in my life, but decided to get creative with this one. One thing led to another, and 6 sets of blueprints later, I have this.

Are you/significant other handicapped? (No offense meant, as my wife is handicapped). No, I am not, nor is anyone I ride with handicapped. But I have had many followers ask me to build them one because of a handicap, or old age. I seriously thought about it, but then I got swept up in life, with marriage, house, job, the usual. I do want to build another one, but not mass production

What's the overall weight on that thing? With all fluids, curb weight is 1310lbs. Heavier than I wanted, but I also added unnecessary beef to the frame. My next trike will be much simpler/lighter.

I don't posess anywhere near the skill or mechanical ability that you and others might have, but is the rad maybe a bit too small (generally speaking - and not necessarily related to your overheating problem). Is the stock water pump "beefy" enough to move all the coolant, since you mentioned its running about twice as far as a standard VFR? I believe that it is, because water is water. The surface friction in the tubes is minimal, so it should be able to push water for a hundred yards without an incline. It actually doesn't have the upward travel that a stock VFR would have, so the lateral distance should be negligible. But it does have to push it up to the GSXR radiator. Speaking of which, the two VFR radiators were not enough, but the GSXR radiator has been great so far. Just recently I had the overheating problem, normally it runs between 150-180F. Seems that the problem is that the hot water is not getting pushed out to the radiator.

Inquiring minds want to know. Or just annoy you. Ask away, I like talking about it.

 

There's not much to go wrong in the water pump; all that is in there is an impeller fixed on a shaft. Water pump failures usually occur due to the seals failing and causing it to leak, but I can't imagine this would slow the pumping/cooling rate. I guess you could check to see the impeller is turning/pumping first as that is an easy check. You can also pull the water pump off the engine (two bolts) without disassembling the pump itself and check that the drive shaft spins easily.

I would go with Toe Cutter's suggestion of a thermostat problem. I replaced mine recently as my bike was slow to heat up and ran colder than it should, because the thermostat was jammed open, and this seems like a pretty common failure. But if yours if jammed in the shut position that would restrict/prevent water flowing to the radiators. Getting the thermostat out is a bit of a mission, you need to pull the air box and throttle bodies off to access it as it is at the base of the V. Of course, that is as mounted in an original VFR, yours may be much easier to get to. Once you've got it out you will visually see if it jammed open, or test it in boiling water to confirm that it opens correctly. Best of luck.

 

Thank you much, CadBury. I got on a thought process of it being the pump, and forgot about other parts that could affect it.

This tells me I've been out of the garage for too long, and my desk jockey job is taking its toll on my years of experience.

I'll check the thermostat after I finish the kitchen remodel, so hopefully this weekend. Happy 4th, to those of you that celebrate it!

 

++++1 with the thermostat :thumb:
A good flush would help too.

 

Well, got it all done. Other than finding homes for the all the tubes and wires, the job was pretty simple and straight forward. I flushed everything out, and got dirty water, and what looks to be cardboard pieces. Strange. But I do got a question.

The new thermostat looks exactly the same as the old one, and says NC82 on it, which is 180°F. Sounds right, but the gauge has to get up to 220° before I feel hot water flowing through the pipes up to the radiator. Once I feel the hot water running through, the thermostat drops to 160ish within 10 seconds. It slowly climbs back up to 220, then drops again to 160ish. The whole time, the bike is at cold idle, revving what feels kinda high. (I have a GSXR tach, which isn't 100% accurate, so I don't know what its actually revving at) I was waiting for it to drop back down to normal idle, but it never does.

I was thinking that I have air in the system, which allows the temp sensor to jump around, but I cant seem to bleed any more out. I've also run it without the cap until it starts pushing water out. Is there a VFR trick I'm missing?

 

I don't know if a 'vfr trick' is going to help with your set up. Any cooling hose/passage above the level of your rad cap can and will trap air. Is the radiator cap at the highest point of the cooling system? (I haven't seen any pics of it) If it is, just keep running it and burping the trapped air out the cap, while monitoring the engine temp. If the rad cap is low or the system is complex, I'd recommend using a cooling system air lift. They work great and almost guarantee an air pocket free coolant refill.

 

Man, now that I think about it, there is something higher than the rad cap. Its the junction where coolant goes to the throttle bodies, which explains the high idle and temp sensor readings. Its bled out before, so I'll just keep trying I guess.