1951 Pontiac Chieftain

[PhilA]

I just ordered the base model- the II provides higher voltage from 4000-7000 RPM, so that's chocolate teapot and wasted money for me. The III has a rev limiter built in but they didn't have a fitment option.

I'm just hoping it can go as low RPM as my engine likes.
High isn't an issue.

The unit itself appears in the photos to be epoxy potted so that's a good start over the Sparkrite. Looking at @sic and his one he took apart- unimpressed. This was $96 versus the $55 (once you factor in shipping) for the SX4000 so hey. If it works, it works.

Phil

[PhilA]

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"Fits dual points distributors"

No

But, now it fits. Car runs a lot better

[PhilA]

Rainy day today.

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Doesn't misfire in the rain now, which is nice. It's a good all rounder vehicle. Makes some people surprised to see a classic out in the rain.

[PhilA]

Saturday.

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Gearbox in bits again.

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Reason:- remove governor, inspect, clean and repair as necessary. Turns out it really wasn't bad but got a bit of a polish and a very thorough clean.

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All back together and it made it all a bit more smooth, for a little while. Still up to the same tricks though.

Sunday

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I had been looking at this picture of the gearbox case with the valve block and governor removed, thinking possibly that the valve block wasn't making very good contact and leaking between passages.

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The manual shows the purpose of all the drillings.

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Looking at the witness marks it appeared as though the area in red wasn't making good contact, possibly allowing leakage between the two arrowed ports.

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Thinking on it that an internal leak could cause odd behavior, I cut a gasket out.

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Sadly I know by heart the tools I need to remove the valve block.

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I fitted the gasket and while it's certainly made an improvement it still does the same thing meaning that really only it can be one thing:- The hydraulic oil. Dexron is about SAE 10 weight. Hot, it's definitely going to be quite thin and the oil sits static in the valve block and stews, getting real thin and leaking by more than acting upon the pistons.
I am going to try a heavier oil and see how that behaves. TO-4 is available in SAE 30 weight so I can give that a try, though likely it'll get engine oil first as a test because that's a fair bit cheaper.

Phil

[Hooli]

You'll be able to setup a specialists for these boxes by the time you're done.

[SiC]

What about one of those snake oil Lucas products that thicken up the oil a bit?

[PhilA]

What about one of those snake oil Lucas products that thicken up the oil a bit?

Tried that, and as with most of these things, it did bugger all.

[SiC]

What about one of those RTVs that is for sealing gearbox pans? I can't remember the loctite code but there is one that doesn't dry in ATF. So any excess doesn't block passageways but the rest does the sealing.

[SiC]

I can't remember the exact loctite number now but it was one of their anaerobic sealants. I bought some as a recommendation from Saab when I was going to replace the valve block on the 9-5 I had (but I never got around to it). Might have it in my garage at home somewhere to read the code off. But was designed for transmission use as it'll dry on the mating surfaces but not clog the fluid paths in use.

[PhilA]

Internally, I think I'm good for seals.

Externally, well....

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