Major Service.

[tunza60]

Hi All, i bought a 2000 Tbird recently..(unseen!!).. It was riding well for a wee while , but has started leaking fuel from carbs..im assuming a float is stuck. Seeing as the bike is so old i think id better get a major service done, and obviously a carb rebuild..leaking front forks too. I have bought the parts..My question is apart from a major service/valves etc.. what parts should i especially look at ?..apart from all the Service book requirements? Which parts fail on 20 year old Tbirds?

thanks for any advice..

tunza in Oz.

 

[atomsplitter]

Obvious things are hoses and cables. Switching to stainless braided brake lines will improve the feel. Clutch cable should be replaced. If the drive chain and sprockets are showing signs of rust or wear change those. The carb diaphrams probably should be replaced. To do a thorough carb cleaning you'll need to pull the plug (12) from the idle mix screw and remove the screw (10) before cleaning. That's a factory set piece (why the plug is there) so to get a proper idle mix you'll likely need to invest in a Colortune. That screw if memory serves adjusts air so the further it's screwed in the richer the mix. Best to check your wheel bearings, headstock brearings, swing arm bushes, the list goes on........

 

[JCooper]

I'm not sure if your bike has Keihin or Mukuni carbs. I am more familiar with the Keihins.

The carb bowl gaskets tend to leak with age. If the bike runs good that's all you need to worry about. If fuel is dripping out of the carb throats then you need to attend to the float valves. Piston diaphragms last a good long time.

Change the oil and filter. Be careful unscrewing the filter bolt. It's upside down and you wouldn't be the first to strip the threads trying to turn it the wrong way. If you get the filter from other than Triumph the large o-ring will be the wrong size. For your first time, get the OEM part. The large o-ring can then be reused several times.

You can order just the o-ring from Triumph, pn 3600025-T0301.

Check the valves and adjust as necessary.

The ignition coils are a common problem if you experience a cylinder dropping out. The crank position sensor (pickup coil) is a common cause of stalling when hot and restarting after time to cool.

Change the coolant. I like G-05 coolant. Tighten all the hose clamps. Make sure the fan comes on when it should. There is an over-temp light. You should never see it come on. Test it by grounding the wire on the temperature sender by the cylinder head coolant outlet pipe.

Flush the fluid in the front and rear brakes and the clutch. (There is no cable).

That's all I can think of at the moment... Should be enough to keep you busy for a while!

Oh! The carb bowl screws are JIS, not Phillips! DO NOT TRY TO REMOVE THEM WITH A PHILLIPS SCREWDRIVER!!!

https://www.amazon.com/Vessel-Megadora-900-Screwdriver-Original/dp/B000TG8OTY/?th=1

 

[JCooper]

Just one more thing... A less than perfect ground between the headlamp wiring and the frame can lead to false overtemp indications when things like the turn signals are also using that ground circuit. There is a service bulletin with a fix, if you experience that.

 

[DaveM]

Also try and see how old the tyres are, not worn but actual age as these can also break down if very old and should be checked.

 

[JCooper]

Good point! I had a perfectly "good" 10 year old tire blow out on a trailer as I was bringing a bike home. The bike was 10 years old but only had about 5000 miles on it.

 

[Ithel]

"The ignition coils are a common problem if you experience a cylinder dropping out"

I just want to mention that my 1999 Triumph Adventurer, a very similar model to the Thunderbird, leaked fuel from the carbs when I got it last year. This persisted even AFTER a complete carb cleaning and resyncing. The leak resolved itself when I replaced the ignition coils, either coincidentally or because fuel from the unfired cylinder was somehow slopping back into the carbs when sitting. I mention this because you might try this inexpensive replacement (in both time and money) before moving to the rest. It took me months to get mine running right, as I didn't have the no-how to sync the carbs myself and was flooding the engine constantly after I'd cleaned the carbs. (And I also unnecessarily drained and derusted the fuel tank and replaced the fuel filter and line as I chased down the source of the leaking carbs.) It may be that your bike needs all the work you've suggested, but in my own experience it was a relatively small thing that was the real cause.

 

[rodsridin]

Obvious things are hoses and cables. Switching to stainless braided brake lines will improve the feel. Clutch cable should be replaced. If the drive chain and sprockets are showing signs of rust or wear change those. The carb diaphrams probably should be replaced. To do a thorough carb cleaning you'll need to pull the plug (12) from the idle mix screw and remove the screw (10) before cleaning. That's a factory set piece (why the plug is there) so to get a proper idle mix you'll likely need to invest in a Colortune. That screw if memory serves adjusts air so the further it's screwed in the richer the mix. Best to check your wheel bearings, headstock brearings, swing arm bushes, the list goes on........

View attachment 57052

Before removing the air/fuel mixture screw, count the number of turns it is out by screwing it in to bottom gently. Usually about 1-1/2 to 2-1/2 turns. Then after cleaning replace to that setting.

 

[tunza60]

Hi All, well..update.. I got the bike back from Major Sevice/Carb rebiuld..all good ..apart from quite loud/frequent backfire.. chatting to my Mechanic, he thinks the wee plastic lattice cone and foam ( Part# T2201224-inlet silencer, which are missing) from rear airbox will make the difference..I am gonna swap over the airbox from my 1998 legend to this 2000 Tbird to see if it makes any difference..Any thought guys?? Other causes for Backfire?..i know these Mikunis are prone to this, but this is a touch excessive and Noticeable to the Boys in Blue maybe..

 

[Rexee]

I'm not sure if your bike has Keihin or Mukuni carbs. I am more familiar with the Keihins.

The carb bowl gaskets tend to leak with age. If the bike runs good that's all you need to worry about. If fuel is dripping out of the carb throats then you need to attend to the float valves. Piston diaphragms last a good long time.

Change the oil and filter. Be careful unscrewing the filter bolt. It's upside down and you wouldn't be the first to strip the threads trying to turn it the wrong way. If you get the filter from other than Triumph the large o-ring will be the wrong size. For your first time, get the OEM part. The large o-ring can then be reused several times.

You can order just the o-ring from Triumph, pn 3600025-T0301.

Check the valves and adjust as necessary.

The ignition coils are a common problem if you experience a cylinder dropping out. The crank position sensor (pickup coil) is a common cause of stalling when hot and restarting after time to cool.

Change the coolant. I like G-05 coolant. Tighten all the hose clamps. Make sure the fan comes on when it should. There is an over-temp light. You should never see it come on. Test it by grounding the wire on the temperature sender by the cylinder head coolant outlet pipe.

Flush the fluid in the front and rear brakes and the clutch. (There is no cable).

That's all I can think of at the moment... Should be enough to keep you busy for a while!

Oh! The carb bowl screws are JIS, not Phillips! DO NOT TRY TO REMOVE THEM WITH A PHILLIPS SCREWDRIVER!!!

https://www.amazon.com/Vessel-Megadora-900-Screwdriver-Original/dp/B000TG8OTY/?th=1

Having fits with left carb on 2002 America. Got the bike, told it needed carbs overhauled, so I completely cleaned and replaced internals. What a mess! Left carb leaking from drain and drain screw. Replaced drain screw, still leaked, so plugged it with proper JB Weld. Then discovered another big leak from the metal fuel t-fitting tube. So separated carbs and pulled apart, freeing that t-fitting. It was loose fitting. The o-rings were shrunken, dried and brittle. One broke apart as I was removing them. Replaced the o-rings put a little silicone grease and try to reassemble tomorrow. Any tips?

 

[sikatri]

Having fits with left carb on 2002 America. Got the bike, told it needed carbs overhauled, so I completely cleaned and replaced internals. What a mess! Left carb leaking from drain and drain screw. Replaced drain screw, still leaked, so plugged it with proper JB Weld. Then discovered another big leak from the metal fuel t-fitting tube. So separated carbs and pulled apart, freeing that t-fitting. It was loose fitting. The o-rings were shrunken, dried and brittle. One broke apart as I was removing them. Replaced the o-rings put a little silicone grease and try to reassemble tomorrow. Any tips?

If you run ethanol gas consider switching to ethanol free. Ethanol damages o-rings and aside from attracting water can damage older carburetors.

 

[Rexee]

If you run ethanol gas consider switching to ethanol free. Ethanol damages o-rings and aside from attracting water can damage older carburetors.

Yes, I have been using ethanol free gas for some time. Got it up & running today. Thanks.