C
cbouton
Member
A little back story first, I have a 12 nytro mtx 153 that I bought brand new in march 2012 and since purchasing have been slowly modding it, mostly handling upgrades and only mechanical upgrades are mpi 180 turbo, ulmer clutch kit, and pc5 pti from oft racing. At about 600ish miles I came across a good deal on ebay for the turbo and pulled the trigger on it. Once I received it I debated having my dealer install it or doing it myself, I consider myself fairly mechanical savvy but didn't want to hurt the motor any so I asked my dealer how many turbo kits they've installed and they said they had did one like seven years prior on a rx1 so I decided to do it myself, figuring I can read instructions just as well as them and not pay the labor to do it. With the help of here the install was very straight forward and actually easier then anticipated. Machine ran great other then clutching from ulmer took some tweaking.
Now for my dilemma, towards then end of the first season with the turbo I noticed a strange idle condition developing where it would idle rough and low rpm's at first start up of the day and once warm ran normally. Figured it must have been a vacuum leak/ spark plugs. Over the summer started diagnosing problem and hit a dead end/ put it on the back burner. Come beginning of this winter I decided I wanted to up the boost and contacted Oft Racing for their spooled up kit, after several communications with rick decided to go for it, and turned out things were slow for him and he actually offered to install the headshim/spooled up kit. So I loaded it up and took it to him for install. Once he finished he had informed me when he was removing the head and installing arp head studs that he had to drill a few of the stock head bolts to get them out, which would indicate it had overheated before, but everything visually looked fine as far as head/pistons/cylinders. Had me puzzled considering the temp light had never came on and im diligent about using scratchers. Since it was only November at this point and still no snow decided to take machine to a dealer to diagnose the idle issue. Not same dealer I purchase from this one has lots of experience with turbo nytros, and upon checking all vacuum connections/ electrical with no avail they did a leak down test and two of the three cylinders had over 25% leak by, and they said it could be valves or rings which broke my heart considering at this point the sled on had just over 1000miles!!!!
Upon my approval they tore the engine apart to locate the issue. They had the head and the block sent to a machine shop to have checked out, which led to all new valve seals and all valves reseated. The block was within spec and all cylinders were round and not ovaled no scoring or gouges. At this point the dealer installed new piston rings and reassembled. Upon firing up the machine still idled like poop, they did another leak down test and center cylinder was still around 25% ish leak by and I believe it was mag side was around 20% ish leak by. Needless to say at this point every one involved was baffled and the next course of action was to order a new block and pistons$$$$$$$$$$$ I had asked them at this point if Yamaha could do anything for me be it good will some parts or discounted parts price, but..... of course was denied. So now the bill is up to $5k in parts/labor to repair a motor that only had 1000 miles on it.
Once turboed the machine was only set at 6psi boost and always ran premium with half a bottle of torco accelerator mixed in. Installed gauges same time as turbo and was always spot on afr and boost.
My question would be what could have caused this/ how to prevent it in the future.
Sorry for such a long post but trying to be thorough.
Now for my dilemma, towards then end of the first season with the turbo I noticed a strange idle condition developing where it would idle rough and low rpm's at first start up of the day and once warm ran normally. Figured it must have been a vacuum leak/ spark plugs. Over the summer started diagnosing problem and hit a dead end/ put it on the back burner. Come beginning of this winter I decided I wanted to up the boost and contacted Oft Racing for their spooled up kit, after several communications with rick decided to go for it, and turned out things were slow for him and he actually offered to install the headshim/spooled up kit. So I loaded it up and took it to him for install. Once he finished he had informed me when he was removing the head and installing arp head studs that he had to drill a few of the stock head bolts to get them out, which would indicate it had overheated before, but everything visually looked fine as far as head/pistons/cylinders. Had me puzzled considering the temp light had never came on and im diligent about using scratchers. Since it was only November at this point and still no snow decided to take machine to a dealer to diagnose the idle issue. Not same dealer I purchase from this one has lots of experience with turbo nytros, and upon checking all vacuum connections/ electrical with no avail they did a leak down test and two of the three cylinders had over 25% leak by, and they said it could be valves or rings which broke my heart considering at this point the sled on had just over 1000miles!!!!
Upon my approval they tore the engine apart to locate the issue. They had the head and the block sent to a machine shop to have checked out, which led to all new valve seals and all valves reseated. The block was within spec and all cylinders were round and not ovaled no scoring or gouges. At this point the dealer installed new piston rings and reassembled. Upon firing up the machine still idled like poop, they did another leak down test and center cylinder was still around 25% ish leak by and I believe it was mag side was around 20% ish leak by. Needless to say at this point every one involved was baffled and the next course of action was to order a new block and pistons$$$$$$$$$$$ I had asked them at this point if Yamaha could do anything for me be it good will some parts or discounted parts price, but..... of course was denied. So now the bill is up to $5k in parts/labor to repair a motor that only had 1000 miles on it.
Once turboed the machine was only set at 6psi boost and always ran premium with half a bottle of torco accelerator mixed in. Installed gauges same time as turbo and was always spot on afr and boost.
My question would be what could have caused this/ how to prevent it in the future.
Sorry for such a long post but trying to be thorough.