470 has problems

[rmcnelly]

The 470 has approximately 1350 miles since Eddie built it, following the seized rod situation.

I took the side airbox cover off on the way home from work today, still unsure if I'm a little rich or lean. 5 miles into the commute (73 degrees and sunny) I'm in the HOV lane at 70mph, and roll on the throttle. The bike rolls up to 85 quick, then slows like it's starved for fuel. I let off, and the bike seems to run ok, so I roll on it again, this time the bike slows at 80mph. So I cruise at 65 wondering what the problem is. I pull over to put the airbox cover back on and notice the coolant overflow is 3/4's full (I've never seen more than a little in there). Back on the road, the bike will pull again past 85, but I ride the rest off the way home at 65. The coolant level never goes down, and the overflow tank is completely full when I get home (the commute is less than 15 miles total).

The bike doesn't seem hot, and the fan does not come on if I let the engine sit (not running) with the key on. Oil level is half way on the dipstick after waiting 4 minutes.

I start it up again, and watch the exhaust. As I rev it up, there is light grey, white smoke beginning to get thicker the more I rev it. The coolant overflow is bubbling in synch with the revs.

I'm depressed and don't have any money left to spend repairing the bike after my soon to be ex shafted me on the income tax this year.

What is the diagnosis?

I've got to go out but will check here again late this evening.

[300lbsgorilla]

Had a similar problem with mine, didn't run hot but blew out fluid. It was a head gasket problem where some of the combustion chamber gases were leaking and over pressurizing the coolant and blowing it out the overflow. New gasket, no problem.

[William1]

Man, that does suck! Hopefully, a new head gasket will get you on your way again. If you have the resources to check for flatness, I would do so. Avoid running it as boiling coolant can eat away at the aluminum in the combustion chamber and the top of the piston. Do not be surprised if the bike is fine when cold. You may even be able to get away with re-torquing the head bolts, but if the gasket leaked, it now has a weak spot.

[blt]

Hope it's an easy fix

[Wayward Son]

sounds like it may have pushed the head gasket when it went lean.

before you get to involved,drain the tank and make sure the rad is full up to about 1 inch below the neck and go ride.

if it fills up the tank again,its probably the head gasket.

if it doesnt,it may have just epxelled excess coolant when it go hot becuase it was lean.

[vanram]

If it is bubbling in ther when you rev it, it is probably the head gasket. With the big bore, put permatex copper coat on the gasket the night before install. Check for obvious problems, flatness, nicks, scratches etc. Reinstall gasket taking care not to touch the surfaces after they have been cleaned with lacquer thinner/gun wash and torque head bolts to spec in 10 lb increments with oil on the threads of the bolts. Thats about all I got. Hope this helps. Good Luck vanram

[rmcnelly]

Yes, the bubbling in synch with the revving seems to spell head gasket.

Eddie, I'll try your suggestion first. If it is the head gasket, will this test cause any further damage?

[Wayward Son]

no,it wont.

[rmcnelly]

Ok, I'll test it later in the week and post the results.

[Mr_Black]

You should be able to change a headgasket on one of these bikes in a couple hours or less.

Good luck McNelly.

[Crfonda]

i am experiencing a similar (if not the same) issue with the same kit on my bike.

i took my bike in and the shop did a leak test but passed... so they ruled out the head gasket.... what else could it be?

the red temp light doesnt go on, but the coolant res get full and dpits out coolant at the end of a ride.. motors runs nice and strong though...

i am thinking about putting the rad fan on a switch and having it on almost all the time...

[smcalpac]

Dan, have you checked the water pump possibly. When I felt your radiators on the ride, they felt almost cool, like they weren't even being flowed through. Start the bike up, let it warm up then grab the outlet hose and squeeze it slightly with one hand, then grab some throttle with the other hand. You should feel water flowing through the hose.

[NMdesertRacer]

Maybe a bad thermostat or radiator cap?

[Crfonda]

Dan, have you checked the water pump possibly. When I felt your radiators on the ride, they felt almost cool, like they weren't even being flowed through. Start the bike up, let it warm up then grab the outlet hose and squeeze it slightly with one hand, then grab some throttle with the other hand. You should feel water flowing through the hose.

ill try that sam. is the outlet hose on the bottom of the right rad or is it on the left....?

i brought up the WP to the shop but they ruled it out pretty quickly...

do you think having the rad fan on even at low temps is a good idea?

[Wayward Son]

i am experiencing a similar (if not the same) issue with the same kit on my bike.

i took my bike in and the shop did a leak test but passed... so they ruled out the head gasket.... what else could it be?

the red temp light doesnt go on, but the coolant res get full and dpits out coolant at the end of a ride.. motors runs nice and strong though...

i am thinking about putting the rad fan on a switch and having it on almost all the time...

no,your bike has a 470 big bore.not a stroker and big bore.

rmcnelly has a 94mm bore with +5mm stroker.

you have a 97mm big bore with a iron liner.the head gasket is leaking!it wont always show up with a pressure test unless it completely pushed out.

cylinder running pressure at rpm is way higher than just pressure testing.

[smcalpac]

Dan, the water pump housing (right side of the bike) only has 1 hose on it. That is the hose that you should feel for pressure. Although it seems as Eddie thinks it may still be your head gasket and he has alot more experience!

[Crfonda]

no,your bike has a 470 big bore.not a stroker and big bore.

rmcnelly has a 94mm bore with +5mm stroker.

you have a 97mm big bore with a iron liner.the head gasket is leaking!it wont always show up with a pressure test unless it completely pushed out.

cylinder running pressure at rpm is way higher than just pressure testing.

eddie what if my coolant looks clean - like no oil in it....?

would i need the head gasket AND base gasket??

[Gravel]

cylinder running pressure at rpm is way higher than just pressure testing.

Yup..

Eddie, have you ever used a combustion leak tester kit, I would think it is much better suited for diagnosing this type of problem.

[Wayward Son]

eddie what if my coolant looks clean - like no oil in it....?

would i need the head gasket AND base gasket??

just head gasket.

it would only have oil in the coolant it it were leaking at a oil galley.

im most cases it just pressurizes the cooling system at high rpm.

[Crfonda]

and what would the white smoke coming out of the exhuast on downshifts be??