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Austin healey block

JTSchmid

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Getting my engine block ready for assembly and was wondering about replacing the small brass plugs in the water jacket. I believe there are seven of the near the top of the block. Is this a concern or should I leave well enough alone?

Thanks in advance,

Jim
 
Well:
If they are old yes do it now.
Because in the car particularly with the one at the rear of the block will be much easier to replace.
 
If you are referring to the freeze or casting plugs, they likely are not made of brass. Usually, they are made of steel and do corrode, especially from the inside.

I went through this earlier this year. The engine was out of the car, and it would have been easy to change the plugs then. But I did not realize that several of the plugs leaked until the engine was installed and filled with antifreeze. There are two rows of plugs on the side of the block and two plugs at the back of the block. One can change them with the engine in the car - all except for the upper one (in the head?) at the rear of the block. The lower one at the back can be done by working through the space between the firewall and the transmission/bell housing. If in doubt, definitely do this before installing the engine; it would take one-quarter of the time.
 
Getting my engine block ready for assembly and was wondering about replacing the small brass plugs in the water jacket. I believe there are seven of the near the top of the block. Is this a concern or should I leave well enough alone?

Thanks in advance,

Jim
I replaced all mine for "just in case" cause the blocks oldand to get a more thorough block cleaning. Not hard to do and I think I got them from AH Spares.
 
There's a casting plug on the rear of the 'log' intake manifolds, and a carb backfire can blow them out (ask me how I know). I managed to get it back in, and put some JB Weld around the edges to help keep it there.
 
JB Weld is wonderful for many things!

When I last overhauled my BJ8's engine--many years ago--the machinist put an epoxy around the edges of all the newly-installed casting plugs. He builds engines for racers, and I figure he knows a thing or two (he also used brass plugs).
 
Surely the small brass blanking plugs are in the ends of oilway drillings and I'd not only remove them, but also use bottle brushes to make sure the oilways are clear of any of the detritus from machining. There's a chap on Healey experience who didn't do this and he got 100 miles before another build as did I. I bought a rebuilt engine from LA and it too, failed very quickly thanks to the oilways not being cleaned out.

The core plugs (from the casting process) into the water jacket are Zinc and passivated so look yellow like brass and they need replacing to because, as has been said, they rust too. There's an engine in my workshop with just that problem.

fit a new oil pump too, they wear out.
 
When I last overhauled my BJ8's engine--many years ago--the machinist put an epoxy around the edges of all the newly-installed casting plugs. He builds engines for racers, and I figure he knows a thing or two (he also used brass plugs).

I did the same thing on the BN4. That might make the freeze plugs a bit more difficult to remove in the future, but it helps prevent other issues like popping out or leaking around the edge.
 
Even if the pump was producing good pressure at tear-down?

They seem to wear and score easily Bob, so I'd be surprised if it didn't need replacing, but you can check it against the manual and if it's not scored and obviously worn out, re-use it.
 
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Visuals.

IMG_0816.jpg


IMG_0822.jpg


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Using a slide-hammer to remove an oil galley plug.

IMG_7613.jpg


Scrubbing oil galleys to main bearings.

IMG_7633.jpg


IMG_7637.jpg


IMG_0859.jpg


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This oil pump has been treated to a dry-film lubricant polymer coating.

IMG_1041.jpg
 
Don't go cheap on the brushes for your block cleaning. The ones I got from HF shed their bristles very easy and fortunately I caught the problem right away.
 
Randy,

I see you have a 100-6 oil pump there. I hope you do not have that pump in your engine. Are you aware that there was a BIG reason that Austin changed from the rotor style to the gear style oil pumps.

Richard
 
Randy,

I see you have a 100-6 oil pump there. I hope you do not have that pump in your engine. Are you aware that there was a BIG reason that Austin changed from the rotor style to the gear style oil pumps.

Richard
Granted, I don't run the RPMs you do__or for sustained periods__but I've been doing okay with the rotor-type pumps for coming up on forty (<39) years.

Even all my BMWs use rotor pumps, including a double rotor (scavenging & pressure) in the case of the S-54 engine'd 01 M Rdstr.

IMG_7794.jpg


Turned up this picture while looking for the oil pump; describes some of the polymer coatings I use. Both of the oil pumps shown in this thread utilize the DFL on internal surfaces, and a thermal dispersant on their exteriors.

IMG_7122.jpg
 
BMC strengthened the pump drive shaft when they switched to a gear type, which means that it's fine to use a vane type as long as you have the stronger shaft. Previously it could bust on a cold day.

Overall efficiency is about the same, but vane pumps pump more at low rpm and they last a lot longer than the geared BMC effort. They're not recommended for racing engines where revs are constantly above 5000.

Check out SC Parts (Germany) or Dennis Welch for verification.
 
BMC strengthened the pump drive shaft when they switched to a gear type, which means that it's fine to use a vane type as long as you have the stronger shaft. Previously it could bust on a cold day.

Overall efficiency is about the same, but vane pumps pump more at low rpm and they last a lot longer than the geared BMC effort. They're not recommended for racing engines where revs are constantly above 5000.

Check out SC Parts (Germany) or Dennis Welch for verification.
Well, sign me up as the fortunate recipient of dumb luck; both my own car, as well as Jim/Leonard's Longbridge 100/6 have BJ8 cams (mine was used as a blank for the Isky T3 grind) and therefore required the use of the later drive spindle (the BJ8 cam has a smaller drive gear, necessitating the use of a spindle with a matching larger diameter gear).

Every car I've owned, all the BMWs and a dozen-and-a-half MGBs (and a 231" Buick V6 I put into a BGT) all used a rotor design oil pump, and I've yet to have an oil-related engine failure__oh, I've had other engine failures, but never due to lack of lubrication.

Thanks for the clarification though, as I didn't remember the detail difference about the shaft__I knew they switched to the geared pump with the 3000 (29D engine in my car since '84; new rotor oil pump from SC installed during initial rebuild).
 
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