Pull engine switch replacement

Neicy · #1 (**permalink**) 07-21-2005

I have a discontinued Volvo MD7A and the handle part is missing from the "kill engine
switch". Have tried several kinds from hardware and auto parts places. None fit.
Since this is from 1977, does anyone have any ideas what might fit or where to get a
replacement.

Neicy · #2 (**permalink**) 07-26-2005

Actually its just the threaded knob or handle
that makes the pull engine switch easier to grab onto. The threaded part that exists
is about 3/16 measurement.

pjfsail · #3 (**permalink**) 07-30-2005

I have an Volvo-Penta MD3B and find that some bolts and nuts are U.S. Standard threads and some are metric. Have you tried a metric thread on your part? If not, I would suggest trying a metric threaded part. Most hardware stores carry metric threaded nuts and bolts in their stock. I hope this may help you.

RichH · #4 (**permalink**) 07-31-2005

Look carefully at the head of the bolt that you are replacing. You will see embossed ''marks'' across the top ... indicating the *strength* of the bolt. Hardware stores usually dont carry ''strength listed'' bolts ... just much weaker- ''common'' bolts. With a common bolt you risk breaking it off when you tighten to the proper torque. A top quality automotive supply/parts store will be able to help you match the ''strength''.

pjfsail · #5 (**permalink**) 08-05-2005

Rich, he is looking to replace a handle for the kill switch. He doesn''t need a grade 8 bolt for that. Miner''s Ace Hardware, in our area, carries grade 3, 5 and 8 bolts. My recommendation to the original author was to try U.S. Standard (course thread), U. S. SAE (fine thread) and Metric thread. My Volvo-Penta (made in Sweden) has all three installed on it. By trying all three types of thread is one way to determine what thread has been used and then he can make up a jury rigged handle from there. Another way to determine what thread is being used is to purchase a thread gauge from a tool company or automobile parts store.

Neicy · #6 (**permalink**) 08-05-2005

Thanks for all of your suggestions. Actually I have tried numerous knobs from speciality hardware stores, Lowes and H.Depo. They are either too small or too large. I have one I picked up at Automotive supply and it has a set screw. To make it work I would have to drill a small indention in the engine switch.
I was hoping to find someone that had maybe repowered (the engine is 1977) that still had the switch. I just want it to be easier to pull with sweaty hands without getting a rag for grip. I will try all of your suggestions and get back to you. Thanks!

Neicy · #7 (**permalink**) 08-07-2005

P.S. The he is a she!!

pjfsail · #8 (**permalink**) 08-07-2005

Sorry Neicy, I didn''t recognize the gender of your name. My thinking is, once you identify the threads of the missing knob (by measuring the part the knob screws onto) you will be able to buy what you need from http://www.newmantools.com/index.html. There are several ways you can determine the diameter and what thread the shaft is. One way to do this is to try a variety of different nuts, i.e., U.S. SAE, U.S. Standard, U.S. machine screw and metric. Or you could buy a thread gauge for U.S. threads and one for metric threads. Thread gauges are very inexpensive and can be purchased at most automobile parts stores. If you can''t find a thread gauge at an auto parts store in your area, an alternative would be a store that sells machine shop supplies. You might even borrow them from a local machine shop if you explained what you needed to do. All machinests would have them in their tool box. Here is a link where you can buy thread gauges, http://www.boltdepot.com. Once there scroll down until you see, "Thread gauges" (in the side bar) and click there. Once you have determined the size of the threads you can buy a knob at http://www.newmantools.com/index.html. I realize it would be much easier to get a knob off of an old engine but if you can''t this is one way to do it. And, you learn a lot about different size hardware. Hope this helps. Regards, Peter

Neicy · #9 (**permalink**) 08-08-2005

Thanks Peter for the more detailed explanation. I am in the process of
determining the thread size and am sure I will have an engine knob shortly!!
Denise

pjfsail · #10 (**permalink**) 08-09-2005

Glad to be of assistance. Please report back and let us know what you did and how it worked out.