Exhaust Tail pipe bolt size

[N9434V]

1970 M20C 

During the process of removing my tail pipe I noted that the washers were absent on one of the bolts.    Upon further investigation I noted that there were two different lengths of bolts.   The bolt without the washer appears to be AN3-13   the other two bolts appear to be AN3-14.      When checking the parts book it did not specifically list the the tail pipe bolts, however the old rib ball muffler shows AN3-15 for all the other ball type connections

My questions  -- 1)  What is the correct bolt size?    Washer placement, is one washer at the head of the bolt and then washers on both ends of the spring correct?  How long is the spring? (thinking the shorter bolts used  may be due to shorter springs)

Thanks for sharing your knowledge

Dennis  

[N9434V]

I found the answer to bolt size  in a previous thread   --  Thanks M20DOC 

 

"It should be an AN3-15 bolt, an AN310-3 nut, a pair of AN 960-10 washers and a 186-218 spring.  The entire tail pipe requires this time 3.  The AN stuff should be stock at any shop, the spring is the same as the ones used in Cessna twin exhaust systems.  Likely easier to find on most fields than a Mooney spring.

Clarence"

[cliffy]

Springs are about $5 from LASAR  I just bought 15 to change out all of mine. Some of the old ones were very short and some were soft compared to the new ones. You may have to "select" fit a couple bolts even though the callout says one size. Change ALL of the bolts nuts and washers. Remember, castle nuts and cotter pins, not fiber/nylon lock nuts. Don't tighten them so tight that you get to spring bind (coils touching).