Overheating/Fuel issues?

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Extram

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Bradenton
So I have an 88 Vmax that has been overheating for a little bit now and I am pretty sure it is the thermostat (which I'm in the process of changing right now). When I take it out for a spin within 5 minutes of it running and driving (never going over 55 MPH nor sitting at stop lights) it will go to the half way mark and get considerably hot but when it is at the half way mark and I am stopped and I try to give it gas it sputters and cuts out. It's not my fuel pump since I just replaced that last week, fuel lines are clean, carbs are pretty clean, and the gas is good as well. Pretty sure that it just doesn't want to run correctly when it's that hot.

Am I correct in my logic that it is actually the thermostat? Radiator is clean, no bent fins, and hoses are clear. Any help would be appreciated. Thanks!

Also where is the best place to buy a thermostat? I've only found two, one for 30 bucks with shipping from partsnmore.com the other 50 bucks from Ebay. Any other place I can go?
 
Is the fan running when it cuts out? If the fan is running, then it is the R/R. Regulator/Rectifier. If the R/R is bad, when the fan is really drawing the amps, the R/R cant keep up, and the bike will run rough and die.

A temp of halfway up, or even more, is NORMAL for a Vmax. There are numerous fixes, a different thermometer, getting the fan to come on earlier, but the Vmax was designed to run on the hotter side.
 
Damn, well looks like I get to put it back together and wait on the R/R to ship in. At least I got to fix my exhaust plates! And the R/R is located near the right passenger foot peg correct?
 
Damn, well looks like I get to put it back together and wait on the R/R to ship in. At least I got to fix my exhaust plates! And the R/R is located near the right passenger foot peg correct?

Close, left side.

Atleast least it is a simpler fix. Dont forget to clean the grounds.
 
Once again it seems like someone is trying to diagnose by guesswork?

Basing decisions on hunches are invariably influenced by whatever your particular prejudice or belief is, or what the 'bloke in the pub' said it was. A good way to waste money on unnecessary parts and time.

There is no secret to good diagnosis - base your decisions on as many FACTS that can be established.
By all means ask for opinions and draw on others experience. Whilst this will be offered in good faith, remember that they haven't seen you bike misbehaving.
Take on board what they say then test the advice by measuring or examination.
If still unsure ask again then re measure or examine the part.

Sorry to start with a rant but I hate to see folk wasting time and money.

To your problem.

Can we assume that the carbs are balanced, fuel filter is clean and has been replaced within living memory, there is no rust in the fuel tank and it idles when up to operating temperature?

You say the motor is overheating. How do you know this?
The temperature indicator will be around halfway on the scale at normal operating temperature and just below the red before the fan cuts in.

From the way you describe the problem it would seem this is happening with the temp. indicator sitting at halfway?
If this is correct then this is not an overheating problem but before discounting it check that the indicator is operating correctly (see the Service Manual for how to do this).

Lets assume that there is a problem then IF it is the thermostat you can measure the temperature at which it opens.
IF it is faulty you replace it if it isn't then save your money.
If it's not that then move on to the next most likely candidate which would be a partial or full blockage somewhere in the core or the radiator. Yours is some 28 years old so after that time there could well be issues.
Is the core clogged with dead flies or mud; are the fins all crushed? Anything that impairs airflow will reduce the efficiency.
As the motor heats up feel for cold spots in the core. It's probably best to remove the stone guard to do this. I've not tried it but an infra-red thermometer may also work.
Try radiator flushing chemicals and reverse flushing. Less likely candidates are cooling fan not cutting in but this should only be an issue when stationary, blown head gasket but I would expect to see coolant being pushed out of the overflow or impellor spinning on the water pump shaft. Hens teeth are more common.

One other issue that I have (rarely) encountered in traffic with high ambient temperatures is fuel vaporisation. This cleared once I was on the open road. Possibly more likely if the cylinder head heat shields have been left off.

If it is voltage related then this can be easily checked with a voltmeter e.g. the R/R whose output can be measured.
Once again, IF it is faulty then replace and save your money if it isn't.

As I said above, the way to ensure a first time fix is to base all of your decisions on the best FACTS that you have available.

You may strike lucky by guessing or going on a hunch but invariably you will waste a lot of time an be poorer.

Your choice.:ummm:
 
Once again it seems like someone is trying to diagnose by guesswork?

Basing decisions on hunches are invariably influenced by whatever your particular prejudice or belief is, or what the 'bloke in the pub' said it was. A good way to waste money on unnecessary parts and time.

There is no secret to good diagnosis - base your decisions on as many FACTS that can be established.
By all means ask for opinions and draw on others experience. Whilst this will be offered in good faith, remember that they haven't seen you bike misbehaving.
Take on board what they say then test the advice by measuring or examination.
If still unsure ask again then re measure or examine the part.

Sorry to start with a rant but I hate to see folk wasting time and money.

To your problem.

Can we assume that the carbs are balanced, fuel filter is clean and has been replaced within living memory, there is no rust in the fuel tank and it idles when up to operating temperature?

You say the motor is overheating. How do you know this?
The temperature indicator will be around halfway on the scale at normal operating temperature and just below the red before the fan cuts in.

From the way you describe the problem it would seem this is happening with the temp. indicator sitting at halfway?
If this is correct then this is not an overheating problem but before discounting it check that the indicator is operating correctly (see the Service Manual for how to do this).

Lets assume that there is a problem then IF it is the thermostat you can measure the temperature at which it opens.
IF it is faulty you replace it if it isn't then save your money.
If it's not that then move on to the next most likely candidate which would be a partial or full blockage somewhere in the core or the radiator. Yours is some 28 years old so after that time there could well be issues.
Is the core clogged with dead flies or mud; are the fins all crushed? Anything that impairs airflow will reduce the efficiency.
As the motor heats up feel for cold spots in the core. It's probably best to remove the stone guard to do this. I've not tried it but an infra-red thermometer may also work.
Try radiator flushing chemicals and reverse flushing. Less likely candidates are cooling fan not cutting in but this should only be an issue when stationary, blown head gasket but I would expect to see coolant being pushed out of the overflow or impellor spinning on the water pump shaft. Hens teeth are more common.

One other issue that I have (rarely) encountered in traffic with high ambient temperatures is fuel vaporisation. This cleared once I was on the open road. Possibly more likely if the cylinder head heat shields have been left off.

If it is voltage related then this can be easily checked with a voltmeter e.g. the R/R whose output can be measured.
Once again, IF it is faulty then replace and save your money if it isn't.

As I said above, the way to ensure a first time fix is to base all of your decisions on the best FACTS that you have available.

You may strike lucky by guessing or going on a hunch but invariably you will waste a lot of time an be poorer.

Your choice.:ummm:

Someone wake up on the wrong side of the pond?
Price for infra-red thermometer---
http://www.ebay.com/itm/Infrared-Th...261497?hash=item2371cf39b9:g:Wz0AAOSw8oFX0DRl
Price for radiator flush---
http://www.ebay.com/itm/Motor-Medic...ash=item1a1283b87f:g:gKkAAOSwO~hXHzhD&vxp=mtr
Price for voltmeter----
http://www.ebay.com/itm/AC-DC-Digit...469791?hash=item281ebe259f:g:bpEAAOSw2x1XLQFg
Price for R/R after diagnosis----
http://www.ebay.com/itm/New-Regulat...ash=item1c45441833:g:iL0AAOSwfcVT~ZXI&vxp=mtr
We know you don't get much sun over there but you could LIGHTEN UP-:rofl_200:
 
Someone wake up on the wrong side of the pond?
We know you don't get much sun over there but you could LIGHTEN UP

Forgive me expressing my frustration - I spent far too many years explaining to motor vehicle Service Managers why I wasn't going to pay for a repair because their technician hadn't bothered to follow the correct diagnostic procedure and had fitted a part 'on a hunch' and that hadn't fixed the fault.

Sometimes you need to have a rant to get folks attention (which it obviously did!)

Just trying to offer some advice and (hopefully) save someone a bit of time and money.
Their choice if they choose to take it or not.
 
Forgive me expressing my frustration - I spent far too many years explaining to motor vehicle Service Managers why I wasn't going to pay for a repair because their technician hadn't bothered to follow the correct diagnostic procedure and had fitted a part 'on a hunch' and that hadn't fixed the fault.

Sometimes you need to have a rant to get folks attention (which it obviously did!)

Just trying to offer some advice and (hopefully) save someone a bit of time and money.
Their choice if they choose to take it or not.

No apology needed- I believe most of us are here to help and I certainly appreciate your advice as I have for years. I rant my myself so it is understood.
I met a Service Manager once. Once.
 
I used to be a mechanic at a VW dealership here in the mid 1970s.
Service managers are the spawn of Satan. Nothing like a SM looking over your shoulder, while you're wrestling with a VW Type 3 muiffler - which was the absolutely worst designed exhaust system ever put on a motor vehicle - and telling you the customer is in a hurry, please work faster...

I will say there is at least one decent service manager out there. The guy at the Kia dealershiop where I take my Soul in for free oil changes, is knowledgeable, and stays out of the mechanics way. He also doesn't try to upsell you on stuff that makes them a ton of money. He seriously came to bat for me on a warranty issue with my Kia Rio, and besides costing me nothing, got a rental car for the 2 or 3 days it took to get the parts here and fix it.
 
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