Would suggest bringing the oil to proper level and installing antifreeze to the cooling system. Coolant draws heat from the motor and is necessary.

Clean the whole area completely and dry. Then run the bike at idle to determine exact where the oil is leaking. Also make sure the cooling fan comes on.

 

I've done a couple test runs around the block for about 30mins yesterday and the day before the oil leak and overheating didnt show up until today. I left my bike at my buddy's shop to have a custom exhaust made for it.

I'll bring some coolant and drain out some of the oil and see how it goes.

 

I'm not a fan of flush chemicals that require driving around. You need to be able to monitor flow and heat buildup while performing the flush.

That said, water with flush in it is going to cool better than coolant (not advocating using just water for normal use). If it's overheating because it's overfilled with oil, then adjusting the oil could stop that, but I doubt it. You've got major internal problems I suspect, with everything you've done and still overheating. Cracked head or block? Extreme blockage in the cooling system? Can you see coolant flowing in the neck (radiator fill cap off) when it warms up enough for the thermostat to open?

 

Yep when i fill through the neck and let it run the coolant level will rise and over flow conversely it will also sink down when the system is drained. For the cracked head/block would other symptoms appear? like smoke out the pipes if either coolant or oil is making it into the combustion chamber?

Im banking on overfilling it with oil. Manual calls for 3.1L i might have gone about 100ml-150ml too much.

at first it was spewing liquid out of the overflow hose which i thought was normal because it was a hot day. then it started spewing steam. I suspect a blockage since pulling out the hoses i found that the PO used some RTV around the inside of the hoses to mate to the fittings. It could have broken off a chunk and lodged itself somewhere in the jackets.

it was doing fine doing short 45min tests but i guess the heat and traffic really pushed it over.

 

When the fan kicks on is it supposed to stay on? On my bike it will kick on for a few seconds then shut off and just goes back and forth but it never stays on for too long.

 

@Sabre-t A local mechanic told me to use this stuff since its design for the tropical climate im in.

 

I can't find any info on what type of coolant this is. It is probably OAT or DexCool type, but without info from the mfg, I'm just guessing.

The flush that is recommended in the "instructions" is slightly alkaline and would generally be safe, but I'm not convinced that sodium citrate based flush will be all that effective on a clogged system. Combined with their flush kit (Prestone Flush Kit) it might be enough to open up a clogged system.

To save wear and tear on the pump, I would not use it more that 50/50. If it is still overheating, there is likely a problem with the bike that raising the boiling point won't help. 50/50 would be a more efficient coolant than the more concentrated ratios.

 

I think i'll bring the radiator to a radiator shop and have them take it apart and unclog it

 

alright @Sabre-t heres my plan of action.

1. I'll have the bike tow'd from my buddy's shop
2. I'll take the radiator and bring it to a shop I know a few guys who'll take the radiator and unclog the channels and solder it back together
3. If the refurbished radiator doesn't solve the overheating I'll buy a new set of heads and jugs have them decked and honed and replace all the gaskets from the base gasket, head gasket, rocker cover gasket.

Im pretty sure if i ever reach step 3. I would have fixed the overheating issue.

 

Let's hope it doesn't come to #3. Before you actually buy a new cylinder head, etc., have a mechanic check things out. It's expensive enough just resurfacing a warped cylinder head, but if that's what it is, you may not need a new one. Same for the cylinders. Maybe only one needs to be replaced if either does. That's a lot of money spent for new parts that might still be serviceable.

 

Sadly there arent any reputable mechanics around here that I would trust. hence why im doing all this myself. the bike was never released locally and as far as i can tell there are only 3 or 4 of these in the whole country. But if i do end up getting to #3 i'll have my cylinders and jugs checked out at an automotive machinist and if they're still good i'll keep them as spares.

I just dont want to go through the trouble of dropping the engine out and replacing the head gaskets and putting everything back together only to find out the heads are cracked.

 

@Sabre-t I am betting its just the headgasket that failed but i really dont want to have to take the engine out and apart more times than I need to.

I suspect the head gasket because whenever i fill the system up with a no spill funnel even after 20 mins the liquid starts to get murky and there are these little bubbles that keep coming up which are most likely exhaust gasses. But then again it could also be a cracked head. The last time I did an oil change it smelled like gas and had signs of moisture in it but not enough for me to suspect coolant was fully emulsifying in the oil

 

Update: I got the back towed back. I drained some of the oil definitely was overfilled at least the oil cleaned up the other side of the sight glass and i can clearly see the oil level. Checked expansion bottle and it was near empty but at the filler the level was just below the thermostat. I did some looking around the hoses and clamps with futile hope hoping that it was just leaking somewhere and to my surprise i did find a small coolant leak at the pipe where the hose joins the rear head. liquid seems to be getting past the O-ring.

The oil leak is still persisting even with the oil level adjust to the proper level. Its coming from behind the front exhaust header and above it. I inspected the cam plugs and they were bone dry so the only failure point i can think of is where the rocker box meets the cylinder head since thats the only bit thats sealed with RTV. regardless i'll have to remove the engine from the bike

 

Update: Brought the radiator to the shop it was indeed clogged up with what seems like little rocks of some kind of sealer. Fingers crossed thats what solves my overheating issue

 

Update: I got the radiator back and it was super clogged with large sediment they said it looked like large chunks of scale they got as much out as they could and the flow is better. I just finished installing it back on the bike and I noticed a leak on one of the heads. the metal pipe with the O ring that joins the hose from the thermostat housing to the cylinder head. the rear head is leaking. and it lines up with how much fluid is lost every time the expansion tank goes empty.


I've replaced this pipe and got a brand new O-ring for it as well. I double checked that the leak wasnt coming form the hose and the clamp . definitely leaking from where the metal pipe joins at the cylinder head.

Any idea how i could fix this? @Sabre-t

 

Update: I got the radiator back and it was super clogged with large sediment they said it looked like large chunks of scale they got as much out as they could and the flow is better. I just finished installing it back on the bike and I noticed a leak on one of the heads. the metal pipe with the O ring that joins the hose from the thermostat housing to the cylinder head. the rear head is leaking. and it lines up with how much fluid is lost every time the expansion tank goes empty.


I've replaced this pipe and got a brand new O-ring for it as well. I double checked that the leak wasnt coming form the hose and the clamp . definitely leaking from where the metal pipe joins at the cylinder head.

Any idea how i could fix this? @Sabre-t

Remind me again what model you have? I'll need to look at a service manual if I can find one, or an online parts exploded diagram to understand exactly what is leaking. Maybe a picture showing marked to show exactly where it's leaking could help.

Hoping the radiator cleaning will solve the other heating problem!

 

Its a 90's 1500 classic its leaking out of p/n 39192 and its o-ring 670. My service manuals have no mention of it

 

OK, check the o-rings to make sure they are seated properly. Are there groves for them to go in? I'm guessing you have a new clamp since you were replacing the hoses. What type of clamp did you get? Maybe a little Vasoline on the o-rings might help, but with those slippery silicone hoses, I'm not sure if that is a good idea or not. With a good clamp, it might be OK.

 

O rings are seated properly on the tube. im thinking they're not sealing on the grooves on the cylinder head side since its heavily corroded. I went with T bolt clamps

 

i think i figured out why its not sealing the silicone hoses i fit are fatter than oem and is causing it to cant to one side and i guess pulling it so it wont seal and seat properly. I put a thin smearing of RTV on the oring and a bit above it to help it seal more

 

I hope that solves it for ya.

 

Update: Threw everything back together. sealed up the leaking coolant pipe. did a rudimentary leak test with a no spill funnel. No more bubbles I believe I have no more leaks and that the blocks/heads/head gaskets are OK. as for the over heating i haven't done a road test because of the leaking cover once I get that sorted out i'll go for a full blown road test but it seems promising.

 

Update: Fixed the oil leak. had to take the engine out did both front and rear just to be safe. Im yet to test the cooling system but with fresh coolant and and after burping the system took it around the block and from what i can tell there is no loss in coolant in both the overflow tank and the radiator.


@Sabre-t do you happen to know how likely an oil pressure sensor would go out or if its just the blub? also i noticed the kickstand doesnt kill the engine.... time to open a new can of worms

 

Update: Fixed the oil leak. had to take the engine out did both front and rear just to be safe. Im yet to test the cooling system but with fresh coolant and and after burping the system took it around the block and from what i can tell there is no loss in coolant in both the overflow tank and the radiator.


@Sabre-t do you happen to know how likely an oil pressure sensor would go out or if its just the blub? also i noticed the kickstand doesnt kill the engine.... time to open a new can of worms

Maybe the kickstand switch just needs cleaning or adjusting. Loose wire?

Not too many oil pressure sensors failing (it's call an oil pressure switch in the Voyager service manual) that I've seen. Mostly comments about the wire connector being loose, or adding an oil pressure gauge. They can fail, though it seems rare. I've had them fail on cars, and they are essentially the same. There is probably a car sensor that could be used in place of the OEM one, if you could find a compatibility chart. There are no tests for it in the Voyager manual, just removal and installation instructions and a test for actual oil pressure that requires a pressure reading tool.

 

On when engine off and no pressure, light turns off when engine is running and is should sense pressure. This means the engine is happy with oil pressure and turns the light off to let you know all things are good.

 

Thanks! so im guessing my oil pressure switch has gone kaput i dont get any lights with key on power. But I tested the circuit and the lights by jumping the connector to ground. lights come on so it wasnt the bulb or faulty wiring. Weirdly though when I jump the oil pressure switch connector both the coolant light and oil pressure light come one. I know they share the same ground as per the wiring diagram

 

Update: I've replaced the oil pressure switch. oil pressure light lights up as normal but im not sure if the overheat light and low oil light are supposed to turn on when the engine is not running then both shut off when the engine is running. Looking at the wiring diagram ground from the oil pressure switch goes through a diode and is shared between the oil pressure light and overheat warning light but the overheat warning light also has its own switched ground from the radiator temp switch.

 

I have only seen you refer to your bike as a "90s, 1500cc". If your oil pressure light does not go off immediately after you start the engine, you need to get a mechanical oil pressure test kit and check the pressure. The operating pressure should be ~ 60 psi. The oil pressure switch is a NC switch and opens at 10 psi. Your bike is one of those with the POG and I would not recommend riding it till oil pressure is verified.

 

Oil pressure is good. the light does come off when the engine starts. what im wondering about is the temp light