Fuel tank rattle

Cacti_Ken · Post by **Cacti_Ken** » Fri Aug 31, 2007 11:46 am

I had previously put some 1/8" rubber strips under the fuel tank when I installed it. But I still have a rattle at low idle. I have the tank back out at the present.

Is there any specific place according to a TM where the cushions are to be placed?
I'm just thinking about looking at the bottom of the tank and see where the high spots are and place the rubber strips there.

Post by **wesk** » Fri Aug 31, 2007 12:41 pm

Only the quantity and size of the strips is given. Placement should allow water to drain quickly and dry the area and placement should consider the uneveness of both the tank and the floor.

Cacti_Ken · Post by **Cacti_Ken** » Fri Aug 31, 2007 3:22 pm

Ok thanks, I'll try again and see if I get it right this time.

OKCM38CDN · Post by **OKCM38CDN** » Fri Aug 31, 2007 7:06 pm

In the SNL figure 3-5 gives a rough location... three parallel strips with 2 accross...

Hope this helps...

Cacti_Ken · Post by **Cacti_Ken** » Sun Sep 02, 2007 1:18 pm

I RTVed the rubber strips to the bottom of the tank. Installed it. and tightened the hold down straps. started the motor. I don't have the rattle noise any more. What I am concerned with is the vibration. You can see it and feel it in the steering wheel. I put my hand on the motor and it appears to be smooth. Yet I can feel the vibration in the tub also.

One thing that I was not certain about, is when I installed the flywheel to the crank, I was not certain about how it was taken off. But like I said I don't feel any abnormal vibration in the motor.

Post by **wesk** » Sun Sep 02, 2007 2:10 pm

The rotating mass (flywheel, crank, rods & pistons) is dynamically balanced at the factory. If we disasemble these parts, and then not get them back the same way we disturb this balance. The only real solution is to dynamically balance the rotating mass at every overhaul. This can be expensive at some shops.

Cacti_Ken · Post by **Cacti_Ken** » Sun Sep 02, 2007 3:36 pm

With the flywheel having the two tapered dowel bolts. that tells me it can be fitted one of two positions. I suppose I could take out the bellhousing with transmission and all and rotate the flywheel 180 and see how that works out.