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BIG project - engine swap/replacement

12K views 17 replies 8 participants last post by  Sku-Torr 
#1 ·
Back in November, my 34K miles engine failed on me while on the freeway. Engine gently stalled and could not restart it when warm. Started fine when cold but lost all power a few minutes later... Did an oil change (after replacing the fuel pump - 2nd time) and noticed very large metal particles clogging the oil filter and into the oil. Clearly, the engine is no longer operational and need to decide on next steps... I have since contacted mechanics in the SF bay and 4 reputable shops turned me down when asked what kind of machine I was trying to fix. I also took the engine out of the frame and now.... stuck!

Any idea where to sign up to buy a replacement engine?

Anybody has leads that could help in this enterprise? Ie. Fixing the engine? I will explore buying one from Yamaha and also see costing options to have a used one shipped from the EU... all this must be carefully assessed in light of cost buying another used Tmax... Thanks for your input on this...
 
#3 ·
I have checked Ebay. Engine are offered in parts, not complete. Will check CL regularly. Wish there was a national database where I could post my request. Salvage companies would then contact me if they can locate one complete engine...
 
#4 ·
I think you're unlikely to get an engine without buying a whole TMAX. Even if you can get a wrecked one for $1000, then you have all that work to do. Might as well just get a used TMAX for a little more money.

Sorry to hear about your issues. My TMAX also has 34,000 miles.
 
#9 ·
Rebuilding an engine is not for the average week end warrior. It requires lots of special tools and experience. I was told by yamaha that a handfull of new engines are offered for the US market annually. The number of engines is very low and never ever seen a Tmax engine offered... options for a new engine are therefore impossible to find in the US... only options remaining : fixing the existing one; find another replacement one; junk the whole Tmax...

Looks like you need to call your Yamaha dealer for your spark plug question
 
#10 ·
o-livier said:
Rebuilding an engine is not for the average week end warrior. It requires lots of special tools and experience. I was told by yamaha that a handfull of new engines are offered for the US market annually. The number of engines is very low and never ever seen a Tmax engine offered... options for a new engine are therefore impossible to find in the US... only options remaining : fixing the existing one; find another replacement one; junk the whole Tmax...
If you decide to junk it, I could some some parts to keep mine going.
 
#11 ·
Symptoms sound like loss of compression? I think? If so then might be a ring job that's needed. Not sure if this would explain the metal bits you found. Hopefully those are from easily replaceable parts and not the cylinder walls. I dunno if that's a thing or not.

Mine is right around 34000 too and still runs great but I don't ride it much since buying a motorcycle. Thinking of selling it. It just sits there and I have to remember to start it once in a while. Might make it my main transport in the high summer. It's nice not to have heat coming off the engine onto you when it's already 100 degrees.

Good luck.
 
#12 ·
o-livier,

If you have the engine out of the bike, I think that some of the hardest work is done... or at least some of the work that is very specific to the TMax. Certainly it is an unusual engine, or not common, but if it is out could you take it to someone who could give you a more telling assessment? Pulling the heads of most engines is specialized, but possibly a Yamaha shop, or competent independent could look at it. Or pull the bottom end (wherever that is) and then crank, rods and pistons. That would answer the rings/ rebuild question.

Depending on your time and skill, you might have a shop do the work on the cylinders and reassemble the bottom end, then you do the other assembly and re-installation.

But it may be that a replacement TMax is the best option on balance. Would, for example, $2,000.00 be too much to spend on it? Can you get a used bike for $4,000.00? What sort of condition are the other bits in? That model has a drive chain, rather than a belt, I think. Its a tough call, I'm afraid. There do seem to be plenty of scooters with many more miles, so it may be worth some time and a carefully considered investment.

Let us know what you decide, or what you learn.
 
#17 ·
Long overdue report on doing an engine swap. Is it the only Tmax at this time in the US that went through a "heart transplant"? Most likely since cost-prohibitive to have a dealer do such work...

I can say it has been a solid project - first for me - and only recommended if you have plenty of free time on your hands… and the Art of Motorcycle Maintenance book next to you. Easy on the coffee, and zen working in the garage! Some details :

• At 32,247 original miles the engine died from overheating back in November 2017. Cause of such was tied to my mistake not securing the primary sheave bolt when doing maintenance. The bolt unscrewed itself and rubbed against the cover.... The engine ran high RPM for about 200 miles (at high speed). Result : the engine overheated and the oil went bad… Upon the oil change, large pieces of metal were found and the oil had a foul smell… Terrible news!
• I decide to take the engine out and spent about $500 in diagnostics at 2 different bike shops, a local Yamaha dealer quoted me $7,800 for fixing the existing engine…
• In March 2018, I found an engine on Ebay for $1500 shipped from FL to CA. The engine was said to have 11,600 miles
• April 27th 2018 - Road-tested... No loose bolts falling off :) Tmax is back for more miles in the SF Bay area
• May 13th, 2019 - Still going strong with now 47K miles. Fork and rear shocks are in need of a "refresh" but no other significant issues… Just realizing I have done about 15K miles in the past year… 90% is highway.
• September 3rd, 2019 : Passed the 50K miles mark. Replaced the belt, spark plugs and filters. Runs like a charm!

Very interesting experience learning how the Tmax is built. Among the surprises, I had no idea the engine is completely part of the frame. Front and rear subframe are mounted directly on the engine.

No video like BWT so apologize for not sharing more on the experience. With patience and the manual, it is totally doable for the average weekend warrior. I did take a lot of photos and short videos along the way to ensure the rebuilt goes "smoothly"…
 
#18 ·
Great News! Finally something positive on this forum, other than Majesties falling apart!!! 8)
 
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