Question about lower unit bolt.

[DennisG01]

I had to research a bit, as well... and each time I do it since I forget... but I seem to recall (click type) that it has something to do with loosening the tension knob at the butt end and then there's an adjusting screw there... or maybe there's a secondary locking nut under the tension knob... something like that. I'll try to remember to take a look. I think I kept the directions in it's case, now that I think about it - so I wouldn't have to keep looking for the directions online each time. It seemed daunting at first, but once I started doing it, it was pretty straight forward.

[99yam40]

at the bottom on my click, it has the locking knob to keep the setting from changing.


headed over to my brothers again today to see if we can find out why the 77 land cruiser will not idle without the choke partially on even after I had the manifolds milled to eliminate the vacuum leaks and exhaust leaks.
Has to be in the carb idle circuit plugged up needing the throttle plate opened more and choke plat partially closed.
I will retorque the manifolds again today after running up to temp to help set the new gaskets.
this thing is a pain to work on.
I did not find any intake vacuum leaks on it yesterday,
the idle cut off solenoid clicks so it should be working, but that does not mean the passage is not plugged up

we shall see.

[TownsendsFJR1300]

This is why I was surprised when that bolt snapped. The service manual is not correct and the motor is a 2019 model. The manual is specific for my motor and purchased through Yamaha. Older versions called for 13 lb. ft. for the long bolt under the trim anode. This generation calls for 30 lb. ft.?? Maybe I had a defective/stretched bolt?? Not following the manual anymore and just tightening snug. Thanks.

Yamaha, on some of their motorcycles have some in-correct torque spec's for different things.
IE, on my '07 FZ6 (600cc), the rear wheel/sprocket mounting bolts (6), are supposed to be torqued to 61 lbs / foot. This is with a self lock nut onto a stud. On another forum(Yamaha MC) , MANY folks, torqueing to this spec, strip out the stud or nut. I stop at 50, no issues..

Another is the oil drain plug. Yamaha calls for 30lbs/ft , steel drain plug/aluminum block. On the FJR model, many a oil sump has been stripped.
On mine, for that same drain plug, I stop at 12lbs/ft. Arbitrary, perhaps.

Just to open another can of worms, Yamaha doesn't post any torque spec's for a water pump housing. The 4 bolts securing the housing down. ??

.

[byron.akhavi@gmail.com]

I am a Chemical Engineer. Specialize in aluminum alloys and composites.

[byron.akhavi@gmail.com]

A torque wrench is accurate within 20% to 80% of the spec. range. Therefore, if you torque 50 lb. ft. a wrench in the 10 to 100 lb. ft. range is ideal. For lower torque ranges, say 5.2 lb. ft. for the lower unit drain plug and vent plug, a wrench with a low range is required (I use a 1-20 lb. ft. ATECH rated for 12 to 240 inch pounds). When torqueing steel fasteners in an aluminum housing, the digital versions that cover the 20-80 percent range are ideal. Also, kissing the fastener after through cleaning is a must.

For the water pump housing, Yamaha's general torque spec. is 13 lb. ft. for an M8 bolt. However, I use 10 lb. ft. for these bolts since it is a plastic housing (80% of the general spec. value). With the Loctite 572, there will no issues with vibration and it's good and snug without damaging the housing (which is very strong).

[DennisG01]

I am a Chemical Engineer. Specialize in aluminum alloys and composites.

I figured as much! All good, though