Cam gallery plug

[Harv]

When the FED engine came back from the machine shop, it had welsh plugs and oil gallery plugs already installed. I left the welsh plugs in, as cooling is not going to be a major drama (running on methanol, for short periods of time, with no water pump or radiator) and the block got a good clean before machining. I did pull the oil gallery plugs though and give everything a good floosh out.

There is an oil gallery plug at the front of the block, adjacent to the cam which should have a welsh plug. Interestingly, the back of the blocks are threaded for a plug. The machine shop had turned up an aluminium plug for the front, as "the small welsh plugs are no longer available". I pulled the aluminium plug with a slide hammer as part of the flooshing process.

After flooshing and drying, I installed new oil plugs. I checked the packets of welsh plugs I had and sure enough no "little plug" for the oil gallery. Hmmm... maybe the machine shop was right. I measured the gallery, and it looked like a 19/32 plug is needed. Some Googling, and I found a packet of NOS brass cup plugs. Life was looking good.

CPC welsh plug.jpg (102.39 KiB) Viewed 965 times

Went to tap in the plug using a socket as a drift and a little tappy hammer. Seated nice, but wound not drive home enough to be flush. Upgraded to the BFH, and got it flush. Managed to smoosh to front lip of the plug, and tear the cup. Swore.

Now have to fish out the plug. Might be able to use them with the cup ground back so it is not so deep.

Question: what are people using for this "little welsh plug"?

Cheers,
Harv

[ardiesse]

Harv,

Them. One of the guys in the Humpy club is doing up his FJ's motor, and he managed to find these welch plugs at a parts outlet close by. I believe that greys and red/blue/blacks use the same welch plug for the oil gallery.

But I don't know about the depth. I've always re-used the old plugs if ever I've removed them.

Rob

[Harv]

Thanks. I've got a packet of them if anyone needs one.

I'll drive the mangled one out, and skim a bit off another one before trying again.

Cheers,
Harv

[Blacky]

Can it be tapped and a plug screwed in ??

[Harv]

Can it be tapped and a plug screwed in ??

Mebbe. But there is a step in there, and the plug would need to sit flush (or embedded) in order not to interfere with the engine plate (the threaded plug at the back of the block can hang out quite a bit). Those plates leak enough without me helping them

Cheers,
Harv

[Harv]

I had grandiose plans of driving the smooshed plug out from the gearbox end of the gallery. Pulled the screwed plug (got antisieze everywhere ), and tried to drive it out with a bit of 3/8” rod. No go. There is a restriction about mid-block. It’s smaller than 3/8”, but larger than coat hanger wire (it’s also smaller than my gun brushes, as I had to clean the gallery from both ends when I flooshed the block).

Before I go buying multiple sizes of rod, does anyone know how large that restriction is?

Cheers,
Harv

[Blacky]

No idea .



Hope this helps




You’re welcome

[Errol62]

I bet someone does......$1.

Sent from my SM-G781B using Tapatalk

[ardiesse]

I don't know, but that's never stopped me from guessing. Here goes -

Mid-block, eh? It makes sense that the oil gallery was drilled from both ends of the block, and in the best tunnelling tradition, the holes are supposed to meet up. But what happens when the drills have been re-sharpened several times? I'm guessing that the holes did meet, but only just; and that was good enough for the block not to be rejected.

I can't say I've ever noticed a similar restriction when cleaning out the oil gallery of a grey block - I used a long piece of 3/8" threaded rod to knock the front plug out of the oil gallery.

What you need is a two-foot-long round file.

Rob

[Harv]

I reckon you are right. The holes definitely intersect, as I can get water through the gallery and coat hanger wire too… just not the length of 3/8 rod I had to hand.

Will work my way down the Bunnings inventory from 3/8 rod. If not, will slide hammer it out and reclean the gallery.

Cheers,
Harv

[Harv]

A trip to Bunnings, some 6.3mm round bar and the plug tapped out.

Went to pulled the original steel plug from one of the spare-parts block. After fighting the screwed plug for 30 minutes, I gave up on the idea of tapping it out with the Bunnings round bar or getting it to tilt out, so punctured it and got it out with a screw and slide hammer.

Photo below shows the uninstalled CPC plug on the left, the one I smooshed the crap out of in the middle, and the original steel one on the right.

cam oil gallery welsh plug comparison.png.jpg (486.58 KiB) Viewed 771 times

Out with the verniers, and the story gets clearer.
a) The original steel plugs are tapered, whilst the CPC plugs are parallel.
b) The original steel plugs have 3 thou of interference. The CPC plugs have 41 thou.
c) The original steel plugs are within 1 thou of being the same depth as the gallery end. The CPC plugs are 24 thou longer than the gallery end.

Drawing below shows the oil gallery end on the left, the CPC plugs in the middle and the original steel one on the right.

cam oil gallery welsh plug.png (3.92 KiB) Viewed 771 times

I've got a handful of the CPC plugs, so next step will be to shorten one to 0.250" long (same as the steel plugs), grease the gallery end (to deal with the excessive interference) and see if I can tap it in without tearing it (precision knockchrometer).

Cheers,
Harv

[Blacky]

As one of my old tradesmen used to say - " you can do anything with the right sized hammer "

[Harv]

As one of my old tradesmen used to say - " you can do anything with the right sized hammer "

Don't force it... get a bigger hammer.

- Harv's School of Tool Abuse.

Cheers,
Harv

[Harv]

Problem solved.

IMG_0762.jpeg (3.42 MiB) Viewed 545 times

Cheers,
Harv

[Blacky]

Handy to know mate , where did you source them ? I am about to start on a fresh donk for the ute - an 1100km trip using 7 litres of oil probably gives me no option Firekraka will attest to how much smoke the old tart blows ….