Throttle hookup for your Merc 300
There are two sources of the throttle hookup you need for your 4 Cyl Merc. Check Ebay item number: 270297360692. This is sold by Mike Downing, a reliable Ebay seller.
There also is a fellow by the name of Ken Hall who has stainless reproductions of the parts you need, excellent quality from Ken, I bought 3 sets from him some time ago.
If you go to my webpage,http://www.boatsport.org/ and click on the Mark 55H parts list you'll find the picture on page 13A to be self explanatory. Look on page 3A and find the part identified as #2, if your motor doesn't have this part you'll need one since it fits in the inner hole on the part identified as # 20 on page 13A and swings the magneto.
Go to
http://www.btmco.com/ or http://www.portagebaysystems.com/marine/ or http://www.boatracingr11.com/sorensenmain.htm
to find a good quality deadman throttle.
Hope this helps.
Throttle etc. hookup is a real easy one.
I use a Merc 400 on my restored 1970 Chaparral 13.5 foot class F hydro with a bucket seat just to motor around on lazy summer weekends.
I had electric start and choke going too. I bought and took apart a used standard Merc throttle/electrical key and choke control box and on a aluminum plate remounted the key ignition and choke button to below my steering wheel. I use the standard Merc engine plugin as stock electrical system even though the motor uses magneto ignition. Located a 12 volt lead acid utility starting battery to the floor in a box behind the slide in bucket seat (removable on tracks so it can go back to a kneeler boat with ease).
The 2 Bowden wires from the original Merc control were cut off and shortened one for the dead mans throttle and the other for the forward reverse shifter linkage. In my case I locked the engine out of reverse but gave it forward and neutral, but it could start in both (neutral or forward) in any case.
I used the original engine linkage and made a metal bracket to hold the action to the outside of the cowl no different from stock use. This allowed the use of the engine unaltered from inside the cowls as it would be for ski/fishing use of the motor. The throttle action is slower and stiffer but its still a deadmans throttle unit. I also attached a tethered to jacket electonic kill switch to kill the engine if you get dumped but on an F hydro with a Merc 400 on the back giving me low 50 mile per hour speeds for that boat dumping it was not a concern at half the power and speeds you could hang on it.
Cost of the conversion was about $25.00 for the used control module with its 16 foot cables and some of my time to easily configure it. There is no reason for the job to be an expensive one and mine really worked well.
*If your not going to use electric start and choke then omit all the electronics except the tethered to life jacket electronic dump out kill switch. Think safety first. With that the price just dropped too.
I used the standard Merc H type chromed steering bar and racing cable steering.
I posted some pictures of this boat fully rigged and on its trailer somewhere on this BRF website too :)
Hope I have been a help. :)
Puddelduck there are others there from UK on here.
Puddleduck: There are other UK enthusiasts on here too like Rod Champkin aka Twister and so on. I know UK s a big country with a load of people but finding out who is around you to help out with their racing knowledge could be a help to you so look them up. They hang around on BRF and could be a source of getting together over there in UK making the scene both exciting and sociable.
Hands across the waters to you from Canada! and it just snowed about an inch here! Arghhhhhhhh!!! :)