01 July 2011

how to "fix a leaky flathead with shop scrap"

The old roadster pickup, "chief", was whipped together for the GNRS show.
Now that I've been driving it some of the half-ass stuff is showing its colors,
really dark oil spots whenever I parked.

oil leak

This was a quick fix that had created a nice oil leak.
There's a 6-volt electric pump from a tractor instead of the stock fuel pump,
so this is an unused hole now.

marks its spot

Stock flathead fuel pumps run on a cammed pump rod,
and the hole has enough pressure to shoot oil up.
Supposedly the later 8ba style can live without the hole being plugged,
but the earlier 59a will lose oil pressure somewhere if the hole is open.

measuring hole depth.

This is something I've needed to correct since swapping intakes.
The earlier fenton didn't have a front oil fill hole,
so this was rigged up a long time ago.
The problem was the oil breather deal blew oil all over the rear of the engine
and the firewall.
There was a rag zip-tied around it to absorb oil for years.

old oil fill plunger plug breather

The new intake is a beat-up Sharp,
and has the road draft tube and oil fill hole in the front like a stock intake.
It's a streetable dual carb version and I can deal with the non-race look.

Another problem was the intake heighth was different 
and the bolt orientation was off a bit.

template time

Last night I had an hour to kill before kid-time,
so decided to solve this problem.

I didn't have the pickup with me,
but took a template off a Thickstun intake that is lying around.


With the template made I looked for some donor scrap.
Fortunately we try to recycle.
I knew the perfect piece was down there.

perfect fit

After some quick cuts and grinding the plate was made.
There was some 3/8 aluminum rod lying around,
perfect for this project.
I had planned on threading some 3/8 steel rod but this is way better.

doubled pic
measuring hole depth

The heighth of the intake measured 2.5".
The thickness of the block at the fuel pump hole is almost an inch,
so there is alot of room for error in making the plug rod the right length.

(i missed taking pics of welding it in the hole so just imagine it for a minute)

Okay now the rod is welded into the plate,
there is an important piece that must be added.
Fortunately I keep hole-saw scraps!

nothing wasted

Using a custom grind hammer I bowled the scrap washer a bit.

good hammer

It was tricky to hammer it without it flying up near my face.


A couple quick TIG tacks and it was strong enough for the purpose.
Its a rip-off of the earlier style flathead fuel rod.

With all the shop work done I was able to finish up at home.
So let's take a driving break.

'67 Grateful Dead.
Good stuff.
Cream Puff War.


Back home to finish up.
Sometimes I use a playing card for gaskets,
but this time I used actual gasket material and some purple "high-tack" sealant.

finding the hole

It's a little tricky finding the hole.
Not a problem,  heck I have 3 kids!

sealed up

Next time I would have made the template off the actual intake.
The shape was perfect for the Thickstun but a little off on the Sharp.
I'm not too worried about it but it is a little hacked.


It is amazing how fast some things can get done.
There was barely an hour to build the contraption,
and maybe 20 minutes to install it.
It almost took longer to type this blog thread!

Next I'm thinking of doing a PCV valve deal in the road draft tube hole.
It looks easy but I've seen many intricate variations,
so stay tuned.


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