Tappet / Rocker Cover Stud / Bolt

[Rod]

Hi All. I have done a substantial search on the site and can't see any reference to a slight issue that I have had for a while and would like to rectify (Yes one of those holiday tasks). I have an alloy tappet cover and the studs / bolts are barely long enough. I would like to to have longer ones.

I bought some longer bolts (high tensile) with the unf thread with the view of running a die down it to extend the thread and then put thread on the other end which goes into the head. I came across two issues when I was about to this. Firstly as the bolts are high tensile running a die down it would not be that successful. Secondly I thought the other end was unc. On further investigation I was told that these are whitworth thread (is this correct?).

With this in mind I turned to option two. I had a mate weld a section into the middle of the bolt / stud and then turned it down. He was able to do it but he advised me not to torque the bolts town too much as he felt the weld would break.

I know many of you run alloy covers. What have you guys done to get the length in the studs?

Cheers

Rod.

[Gman]

Not sure of the proper name for them but, you need nuts with a long shank that goes down into the rocker cover to pick up the thread, would have been supplied with the cover. You could have these made by an engineer.

[DJ]

For nuts/bolts that you don't just find in a hardware store, I've often had success with a place called Specialty Fasteners in Canberra. They stock a lot of unique engineering stuff in HT & SS, & seem to be able to source things that no one else is interesting in.
17 Cessnock St, Fyshwick ACT 2609
(02) 6280 7794

[fe350chev]

Just a quick clarification, is it the case of a lack of thread into the head that's the issue or a lack of thread to bridge the gap to get purchase on the top end. Reason I ask is if you find the right thread at the head end then you could form a sleeved bridge in the centre with a hollow threaded section to act as an extender that nobody sees. As in suspension adjuster rods.  See the pic, where the nuts are, use a hollow threaded piece to joint the fine end if it's a tall cover. Go kart suppliers use these adjuster a lot.

[fe350chev]

this way you can keep the harder to find threaded head end the same and create a linkage rod as in the pics below. This way it's fully adjustable with any future cover. Id advise putting a bit of locktite.