Merc 500?

[Jeff Akers]

Question: I have a 1978 merc 500. Is it a legal block for D stock??? Mod??? :confused:

[nbranews]

Mod - yes. Stock - I don't know. I bet Dave Scott would though.
In NBRA that motor would be legal as an E mod or could be run stock with exaust out the bottom as a D mod.

[RichardKCMo]

By the way,send info as per request.

[Jeff Akers]

Thanks for the info guy's.
Thought I had a good powerhead but the crank was "belly up". Blocks ok though. thanks again .

[hydroc888]

Jeff. How bad is the crank? I have ran them for quite some time with pits in them as long as there is some good surface for the rollers to run on. A few pits dont seem to matter. If there is a flat spot then they are history.

[Merc66G]

But If any of the components in the motor you plan on building mean anything to you, I would advise you not to use that crankshaft. Getting away with running a pitted crankshaft is not a good plan. There are tens of thousands of those cranks out there and they aren't that expensive. settling for good enough will set you up for disapointment.

Just had to give my opinion :D

[Jeff Akers]

No I wont run it, or anything else that is questionable.
Bad crank's make great CRABPOT WEIHGT'S :eek: :D

[mercguy]

No I wont run it, or anything else that is questionable.
Bad crank's make great CRABPOT WEIHGT'S :eek: :D

ah Jeff, just box it all up and you can give it to me at the next race. You don't want that crap! But, I could use another DMH competitor this year. If you need a crank, I have lots of good ones. BUT, once you start "messing" with Mercs, you are not going to want to go back to them OMCbadiers................ :p

[crankbearing]

Question: I have a 1978 merc 500. Is it a legal block for D stock??? Mod??? :confused:

Hey Jeff,

sortry a little late but yes that is a legal block you would need to fabricate a fuel pump bracket for it as you need to run the square style pump in stock.

The other thing to check if that crank is single or double race center main although the single race crank is nicer the double race is the only legal crank that I know of The stubs on top of the crank needs to be 2 15/16" to 3 1/8" if they are shorter than this from the top throw to the top of the threads they are no good for the motor they will not clear the ignition components.

Regards,

[Jeff Akers]

I forgot about this thread...It's been a while;)

Thanks for the info on the crankshaft Dave...I didn't know that..

I ended up giving the usable parts to a D guy in region 10.