351 Ford special spark plug wrench?

[E4ODnut]

We're in the final stages of purchasing a '93 Bayliner 3288 with 351 Ford Windsor engines, US marine conversions.

The Starboard engine still has the original US Marine manifolds, and the Port engine has just had new Volvo manifolds installed.

As part of my mechanical inspection, I want to do a compresssion check, but found my standard 5/8" plug wrench would not fit any of the plugs because of lack of clearance to the exhaust manifolds. There is not enough room to swing a box end wrench on most of the plugs as well.

It seems inconceivable that the heat exchangers and manifolds would have to be removed to change plugs, so there must be some sort of customized spark plug wrench used.
Is such a wrench available on the market, or, if someone has successfully built one, what is the design like?

Thanks,
Robert

[FAST FRED]

Usually the plug socket fits on the plug , and a machined hex head in the socket can be turned by an open end wrench.

Room for this??

FAST FRED

[E4ODnut]

Nope. no room at all. As if the manifolds themselves wern't bad enough, the outboard side of the engines have the fuel tanks less than 6" away, and Stbd side of the engines also have the heat exchangers.

I bought a 6 point 5/8" plug socket, cut 3/8" off the bottom end, so the hex on the plug is still fully engaged. Then I ground the top end to a taper so that the angle is in line with the outside diameter of my 3/8" drive universal joint, so the whole affair is as short and narrow as I can get it.
If this doesn't do it, it's off with the manifolds, but I'm optimistic it will work.

Thanks for the response,
Robert

[gonzo]

They make a plug wrench with a swivel that works for that application. The one I use is made by SnapOn, but there may be other manufacturers. A normal socket with a universal joint is too long and bulky.

[E4ODnut]

Hi Gonzo,
Getting Snap On tools on short notice is a problem for me here.
I bought a 6 point 5/8" plug socket, cut 3/8" off the bottom end, so the hex on the plug is still fully engaged. Then I ground the top end to a taper so that the angle is in line with the outside diameter of my 3/8" drive universal joint, so the whole affair is as short and narrow as I can get it.
If this doesn't do it, it's off with the manifolds, but I'm optimistic it will work.

Thanks to all for the response,
Robert

[E4ODnut]

Update:

The modified socket and Snap On universal joint worked just fine. No problems with any of the plugs. There is a 15 to 30 degree angle on the U joint though, so I'm sure that it would be impractical to try tightening with a torque wrench.

Robert