BritishV8 Forum

I'm putting off the console until I decide if I want to do anything with the sound system but I may wait until winter. The rest is done other than the throttle cable and programming.



Guess I'll make a cover for that hole also. Nuts and bolts for the strut pivots as well. As all of us who do these things are painfully aware, at the end there are always unexpected items that pop up and often cascade into bigger jobs. Such was tidying up the wiring bundle under the hood and putting things in order generally. That blown fuse? Turned out to be caused by a fat diode I put across the relay terminals for the AC clutch. It didn't like 12v and decided to conduct both ways. Since it was one of the last 2 wiring changes I made that wasn't too hard to find. Replaced it with another surplus unknown fat diode and all is well.

I ended up having to modify a support bracket for the relay panel as it was hitting the re-routed plumbing for the surge tank drain. Tedious but not difficult. And so today I think I will be able to add oil and perhaps even coolant.

I do need to go back and research this thread to see if I made any mention of actually putting oil in the compressor. I'm pretty sure I did but I really wish I'd made note of it with a sharpie to remove any doubt. I dislike the uncertainty.

So that's it for now. It was surprisingly difficult to find bulk throttle cable in the right size but it's likely I just never went about it right. I ended up calling Speedway and ordering a 48" cable from them and hopefully it'll be the right stuff.

Here is another example of unobtainium:





This little bugger seems to no longer be in production. It's a shame too, it's a lot nicer than the alternatives. Lights up when blown, has a clear epoxy top with a nice organic rounded shape. They do become dull with age but still look better than the squared off ones.

Jim

Looks great!

Hello all,
After 8.5 years of customizing my MGB, it's finally getting close to being completed. Here are a few pics. Interior and final assembly to go. Hopefully, back on the road in a few months

I had really hoped to complete the wiring yesterday but at least I got close. A blown fuse had me locking up just before I finished. That's OK, I'll do it today.

I just realized, that teflon insulated cable I've been using for sensors reminds me strongly of the sensor wires they use in jet aircraft engines, I wonder why I didn't recognize it earlier? Probably just left over ends somebody is selling on ebay.

So if all goes well today, I can put the console and radio back in, check off the wiring and go on to fluids.

Jim

I did a coat of clear in the engine bay and will do another light coat tomorrow. I'm happy with the look so far and fingers are crossed that the paint will stick. Cleaned the crap out of it, but I've read that the base coat should be sprayed 12 to 24 hrs after spraying the primer or it may peal after 3 to 6 months. I may have missed that window by a day. The point that they make is if you spray within that window you will get a chemical bond. After that window you're supposed to scuff the primer to create a mechanical bond. Did I mention I'm not a paint and body guy?
I did get the Flywheel resurfaced (Horsepower Machine, Bremerton) and it looks like we should be getting the clutch installed pretty soon.

Gotta be about the slowest race on record if it is. I was hoping to finish the wiring today but a new honeydo popped up so maybe not. Spent some time yesterday on wire routing and sleeving, down to the last 4 connectors. STILL waiting on my brake hoses for the sammy. Memphis FedEx SUCKS!

Jim

Not a paint and body guy by any means, but I did get the first coat of base color on and it  needs another to cover everything. Hope we cleaned it and scuffed it enough! We've got the clear coat ready to go.

Quote from: BlownMGB-V8 on July 21, 2026, 10:14:31 AMI know, right? It's the hardest part of the job, almost at the end but getting those last few bits that have been put off because they are the least enjoyable ones. I guess you'll be charging with r134a? Can't wait to find out how well it works. Almost like we are in a race to the finish! My goal is to have it done and dusted in time for my birthday bash at the Cincy meet. Really looking forward to that this year, especially after the last two went a little sideways. Angel Breath just in time for the hot days, right?

Jim, I'm in no real race to get it done. I'll be driving up to Sandusky on August 25th so I'd like to have it working by then. I'm sure there will be some sorting things out, there always is with a big project. Yes, I'm going with r134a. We will see if it works like I hope it does!

I know, right? It's the hardest part of the job, almost at the end but getting those last few bits that have been put off because they are the least enjoyable ones. I guess you'll be charging with r134a? Can't wait to find out how well it works. Almost like we are in a race to the finish! My goal is to have it done and dusted in time for my birthday bash at the Cincy meet. Really looking forward to that this year, especially after the last two went a little sideways. Angel Breath just in time for the hot days, right?

I went old school on the compressor control. A pushbutton on/off switch and an evaporator thermostat with a dashboard knob. Those two wires I thought went forward? Yeah, they go to the ECM, don't know how I missed that. In the bundle they must go down instead of up, very hard to see back there under the shelf. Must have just been tired I guess. I kept trying to think of anything else that might be used in that control line and there was just nothing. Plus, I had already located the relay by shorting one of the ecm connector pins. That would have had to have been the gray one going to the relay control. I will have to double check the gray/red one for signal {12v) on the demand pin. That's the last mystery solved I think. So all I should need in the tune is a way to force the compressor on in the ecm any time it gets a demand signal. I should be able to hear the relay click when it turns on. I need to fish a heavier wire from the relay to the compressor, so that's on for today. Then those wires go in a sleeve to run forward along the frame rail and I can finish it all up. Maybe get done today, maybe tomorrow but I'm shooting for today.

The inside end of the maf cable is done, that was tricky. The sense wire (yellow) carries a frequency signal in the 2khz+ range and the two others supply + and - and originally none of that is shielded. I wanted to shield the signal to remove a possible variable since I expect some trouble from the duct configuration anyway. Normally I'd use a shielded 3 conductor cable there and ground the ecm end of the shield but instead I'm using 2 conductor and will supply the ground with a short wire from the body ground at the power block on the inner wing. I'm leaning towards the body ground as that appears to be the way it was done to start with and could help isolate that ground from the signals. With the sensor generating a frequency it's possible for an image of that frequency to be carried back on the ground, so it's probably better to ground that at the body. Very technical stuff, but it needs to be considered.

Man the body on this car is badly in need of a wash. Probably a good sign that I'm thinking about that.

Jim

Quote from: BlownMGB-V8 on July 20, 2026, 07:05:33 PMBasically similar. I don't have the pressure sensor But I'm pretty sure I can turn that off in the software. I've traced out the circuit in the car except for one device that I haven't located yet. It's in the control circuit between the thermostat and the relay and appears to be in the engine compartment. At the moment I'm at a loss to identify it, I guess that's what I get for getting creative. I'll just have to trace out the wires tomorrow to find it. At the moment I just can't think what it might be.

Jim

Jim, maybe you can play with the pressure values in the configuration in some way? The compressor relay won't be energized unless the pressure is at a specified value. As you know, that's how it is cycled. How are you cycling the compressor without a pressure sensor? 

I'm about two weeks away from being ready to charge the system. I got the compressor/belt/ tensioner installed this afternoon. It's nice to see it spinning at last. 

Scott