Mercury Thunderbolt

JBP · 25-11-2004, 09:16 PM

Just got a Thunderbolt 40, I know it's old but it does work, so what's the history? Where they any good in their time?

Thanks

Jon Fuller · 25-11-2004, 10:25 PM

yeah not bad, how does it feel compared the the 20 on your newen?

Captain Chaos · 25-11-2004, 10:44 PM

a thunderbolt 50 used to be able to kneeboard me and my cousin off a painfully old 16ft cabin "thing" with about 4 peeps onboard.

quality!

Our one stunk of petrol and allways needed new impellers.......Fk nose why?

Jon Fuller · 25-11-2004, 10:47 PM

Quote:

Originally posted by Captain Chaos
Our one stunk of petrol and allways needed new impellers.......Fk nose why?

Is your surname Hopkins?

Captain Chaos · 25-11-2004, 10:50 PM

no its Chaos, why do u ask?

JBP · 25-11-2004, 11:12 PM

Dunno what it's like on the water, gonna see on Sunday.

It won't stay long on the 12ft sorcerer as to race it needs a newer 20hp standard shaft.

Could always crop the thermostat to reduce the pressure on the impeller, might last a bit longer.....

JBP · 25-11-2004, 11:34 PM

Quote:

Originally posted by Matt
Any engine not maintained by Captain 'Lump Hammer' will probably run fine for years.

I'll check for the dents on the casing then.....!

Captain Chaos · 25-11-2004, 11:38 PM

Capt C emergency repair pocedure:

Step 1) In cae of engine stall, hit top of cowling.
Step 2) in case Step 1 fails, Hit engine harder!
Step 3) Kick Tyre and says "she's a lovely runner"

Passed down through 3 generations of chaos that has!

Jon Fuller · 26-11-2004, 08:56 AM

Quote:

Originally posted by JBP
Could always crop the thermostat to reduce the pressure on the impeller, might last a bit longer.....

Confused of Shepperton!

What's this procedure all about?

JBP · 26-11-2004, 09:44 AM

Been told you can remove the thermocouple type bit in the middle to allow full flow at all engine temps, though I dare say it'll stop it from getting upto proper operational temp.
Would that save back pressure on the poor little impeller?

Jon Fuller · 26-11-2004, 09:50 AM

I've never heard of that as a tuning trick.

I do know, that with the bigger stuff, removing the thermostat/restrictor washer, in an effort to improve cooling by increasing the flow, can cause all sorts of trouble, coz the stat/washer gives a resistance at the outlet, thus increasing the coolant pressure within the block, which stops 'steam pockets' forming, these little fkkrs are lethal.

I personally wouldn't mess with the cooling system unless it's a well documented and proven mod.

JBP · 26-11-2004, 10:47 AM

I'll leave well alone in that case, thanks.

Will let you know how well it runs Sunday.

Jon Fuller · 26-11-2004, 11:02 AM

going by your previous post, does the one you just bought have a different shaft lenth?

JBP · 26-11-2004, 01:06 PM

Quote:

Originally posted by Jonny
going by your previous post, does the one you just bought have a different shaft lenth?

looking at the gear box it's not far off the same place as my newer 20, I pick it up tomorrow and hope to try it on Sunday but will check the level of the gearbox in relation to the keel.

JBP · 27-11-2004, 06:27 PM

Quote:

Originally posted by Jonny
going by your previous post, does the one you just bought have a different shaft lenth?

Yes shaft length looks longer, well the gearbox appears to be lower but the plate at the top of the gear box is level with the bottom of the keel.

Not started yet but will try Tomorrow...

JBP · 12-12-2004, 02:51 PM

Quote:

Originally posted by Jonny
yeah not bad, how does it feel compared the the 20 on your newen?

Well managed to breath some life into the engine at last. Ran it up on muffs yesterday but had to de-grease the drive after all that 2st oil came outa the exhaust.

Gonna run it again tommorow and disconnect fuel line & fog it up for winter.

A friend who has a 1950/60s Boston Whaler is interested in it as a classic, not sure myslef though.....

www.wandaoffshore.co.uk