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Valve Drain Pipe

Rreford

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I am tearing down a '67 BJ8 motor. There is a tube below the oil pressure relief that I can't identify in the service manual or other online diagrams. Is this a valve drain pipe I've seen mentioned in some posts? Is it pressed in or threaded in?
 

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Yes, the Oil Pump Bypass Tube/Pipe drains excess oil from the pressure release valve.

And, you can see in both of the slides, it is threaded.

Regards, Bill
 

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Yes, the Oil Pump Bypass Tube/Pipe drains excess oil from the pressure release valve.

And, you can see in both of the slides, it is threaded.

Regards, Bill
Bill, thank you so much - exactly what I needed, they are now removed, bagged and tagged :smile:
 
Hi Patrick,

Its a tool for removing and replacing valve springs and valve seals without removing the head. Has 3-axis adjustability for valve stem alignment and will therefore fit most heads. And, can be used to remove and replace valves with the head off.

Very useful for breaking-in rebuilt old British flat tappet engines. You can do the initial startup and break-in using weaker valve springs (or just the outer valve springs), and then install the heavier service springs (and/or inner springs).

Regards, Bill
 
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Hi Patrick,

Its a tool for removing and replacing valve springs and valve seals without removing the head. Has 3-axis adjustability for valve stem alignment and will therefore fit most heads. And, can be used to remove and replace valves with the head off.

Very useful for breaking-in rebuilt old British flat tappet engines. You can do the initial startup and break-in using weaker valve springs (or just the outer valve springs), and then install the heavier service springs (and/or inner springs).

Regards, Bill
Hi Bill,

My engine wasn’t broken in with the aid of that tool. This is the first time I’ve heard about breaking in a British flat-tappet engine using weaker valve springs too. Not having to remove the head is big plus!

Cheers,

Patrick
 
Hi Patrick,

Most people don't use break-in springs, except for performance engines. But, reducing load on an older design flat tappet cam during break-in helps (especially with the quality of many parts today).

For example, I checked out 12 of the latest Healey lifters and their cam lobe surfaces are flat (slight taper with NO crowning) and their diameters were often over-sized by up to 0.0015-inches by my measurements; about half of them were tight in the bores. They will need to be sized properly and then matched to the cam lobe profile/taper. However, both their side and lobe contact surface hardness did test within factory specifications.

I broke-in the engine in Barbie's TD with 80 pound seat pressure springs and then replaced them with 130 pound seat pressure springs afterwards. We put a lot of effort into her engine (billet crankshaft and rods, JE forged pistons, porting and custom valves, performance cam, high chrome liners, etc). And, it is a very nice and smooth engine with great performance. The engine machining was done by a shop that builds engines for museum restorations.

Collecting parts for the BJ8 engine now. :smile:

Regards, Bill
 
Perhaps not this specific model, but certainly one of the ones that LSM offers. Looks like a substantially crafted tool; impressive (and I'm hard to please).
 
One and the same. And, well worth the money.

Although, I made a few modifications to mine for my specific applications.
 
Hi Patrick,

Most people don't use break-in springs, except for performance engines. But, reducing load on an older design flat tappet cam during break-in helps (especially with the quality of many parts today).

For example, I checked out 12 of the latest Healey lifters and their cam lobe surfaces are flat (slight taper with NO crowning) and their diameters were often over-sized by up to 0.0015-inches by my measurements; about half of them were tight in the bores. They will need to be sized properly and then matched to the cam lobe profile/taper. However, both their side and lobe contact surface hardness did test within factory specifications.

I broke-in the engine in Barbie's TD with 80 pound seat pressure springs and then replaced them with 130 pound seat pressure springs afterwards. We put a lot of effort into her engine (billet crankshaft and rods, JE forged pistons, porting and custom valves, performance cam, high chrome liners, etc). And, it is a very nice and smooth engine with great performance. The engine machining was done by a shop that builds engines for museum restorations.

Collecting parts for the BJ8 engine now. :smile:

Regards, Bill
Hi Bill,
I was very picky with my camshaft & lifters when I overhauled my engine and I ended up going with Elgin. I had three suppliers I selected and interviewed them. Prices varied. Unfortunately, I had to eliminate two of the companies I sent questions to because they did not answer all the questions. Elgin did and when I call Dima, he explained his process in detail. He knew the Austin engines quite well and checking for hardness, etc.
When are you going to rebuild your engine?

Cheers,
Patrick
 
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Hi Patrick,

We are planning to start the full rebuild in about 24 months.

In the meantime, will make a few changes this spring before the best driving season starts. I was doing a tuneup a few weeks ago and noticed one of the rocker arm spacer springs was starting to cut into the rocker shaft. And, decided to rebuild the assembly using the Denis Welch rocker arm spacers and hardened shaft. Waiting on a few shims now to center the rocker arms with a slight offset and adjust spacer clearances.

I really like the rocker arm spacers; there is virtually no friction and everything can be positioned correctly.

Of course, thought this was a good time to check the cam followers and cam lobes. :( Two of the followers had one very small pit and I am changing them too before any damage is done. The cam is still in great shape with full lobe lift at every valve location (0.261-inches). The latest lifters have good hardening, but the machining was off as sold (crowning and diameter).

Rocker Arms Unlimited did the rocker arm rebuild, checked over and crowned new lifters and also checked their hardness. Will use Smith Brothers pushrods (with new adjusters) so everything north of the cam is in like new condition.

I'll decide on the cam to be used in the full rebuild later based on recommendations like yours, but will keep it close to BJ8 specifications. I have a set of MGC cam followers with good hardness and crowning; and Smith Brothers are making the required lifters for those too. Might use them in the full rebuild. They are used more in racing as you know, but some builders say they are not as durable long term on the street.

Regards, Bill
 

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With no data whatsoever, I persuaded myself that a gun-drilled cam that continuously feeds oil to each lobe and the oil pump drive gear is a good idea (all the ZDDP in the world won't help much if it's not getting where it's needed). I got the gun-drilled DWR1 cam, which DW claims is 'a bit better than a stock BJ8' cam. I like it; slightly lumpy but steady idle at 700-750RPM and pulls strongly up to 5K RPM, above which I don't need--or want--to push the engine very often. There is another vendor with a gun-drilled cam, but I don't have a link or remember the company.
 
Hi Bob,

The drilled cam sounds like a good idea. I first saw one for the XPAG from Newman Cams in the UK and considered getting it when we rebuilt the MG TD.

Regards, Bill
 
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