John S's Journal

I finally crossed off a few misc. tasks on my list with a day to spare before the Amity Pancake Breakfast & Car Show. 80 mile trip up from Eugene to a city park for a get together with some fellow Oregon members and a nice variety of classic cars, trucks, and a decent showing of British cars. I’d met a couple of the guys briefly over the course of the last few years before Covid but there were some other guys that I just “knew” from the forum so it was good to put faces to names.

I took highway 99W which is a nice 2 lane road through some small towns in the Willamette Valley. Beautiful day and light traffic so it was a treat to get the GT out beyond the comforts of the local roads that I have been driving as I dialed in the tuning of the car after receiving the original 25D back from Jeff and the rebuilt HS4’s from Joe. Having a chance to experience the OD on a long trip was something that I was looking forward to and it made a huge difference in comfort being able to cruise at lower rpm’s.

A 160 mile round trip with zero issues really boosted my confidence in the reliability of my car so I’m looking forward to just being able to jump in it and go now. Took it to have the front end alignment checked and adjusted this morning and my guesswork after the front suspension rebuild was fairly close. Nice to have it dialed in although it tracked and handled pretty well on the trip.

The list of things to do has narrowed down to finishing the front valance which stalled out after the carbs showed up. It’s in epoxy primer just awaiting some time and motivation to skim with some filler, sand and paint. Then the bumper can go back on. A couple guys at the show said to leave it off to show off the nice, powder coated suspension but it looks unfinished to me so I’ll get to it eventually.

I finally got around to getting the GT up on jack stands so that I could look into whether the solenoid was my problem. I suspected it was the issue since the engine and gearbox went back in and it hasn’t worked since the reinstall. Ohm checked the wire after confirming power wasn’t the problem. After seeing an open condition, I pulled the solenoid and discovered the wire was severed inside the insulation. A little solder and some heat shrink tubing and a re-check with the ohm meter and with 16.5 ohms showing, I put it back in and took care of some other items on my list. Drained and refilled the rear diff, topped up the gearbox oil, tightened all exhaust clamps and then went for a nice long drive. Flicked the stalk in 4th and I got my other gear!

Although it worked when I bench tested it months ago, I always wondered if I did a good job servicing the Craigslist gearbox that I purchased on the cheap. I hadn’t intended on doing anything other than replacing the easy to get to o-rings, seals, gaskets, etc. but that changed when the pump assembly dropped down into the abyss. As long as I had to take the OD unit off, I replaced the o-rings on the pistons as well. Today’s drive reassured me that I didn’t bungle anything up when I reassembled it.

Took my wife out for a ride in the GT yesterday morning to visit a local farm and pick up a flat of raspberries and the car started right up and ran reasonably well other than a slight stumble under light acceleration. Spent a little time afterwards making a couple minor adjustments and then went for a test drive through the city streets to see if I cleared up the stumble and the answer is a resounding “YES!”. My wife is probably sick of hearing about all of my trials and tribulations since the rebuilt carbs went on but once the discovery of the missing restrictor was made, things went smoothly. Now I can concentrate on some other minor issues while still being able to just get in it and turning the key. Finally.

Thanks to a fellow member, the mystery of excessive jet depth on my newly rebuilt HS4’s is now solved. I have been trying to get my GT lined out since I swapped the fresh carbs over and it’s been a hair pulling trial. I could get the car to run well enough for some drives in the country but knew all was not well. Little did I know that the PO had cut off the end of the air inlet pipe on the valve cover, thereby eliminating the restrictor and consequently over-diluting the mixture. Clay Johnston was kind enough to mention a couple things and it dawned on me that I hadn’t checked that piece of the equation. I wound up making a restrictor out of a tapered plastic cap from a small bottle of Loctite by drilling a 5/64” hole in the end and trimming the other end so that it would slip into the part of the way and then slipping the canister hose back onto the pipe with the restrictor inside. Set the jets 2 full turns down and the car started right up and ran smoothly. Raised the jets up 2 flats to see if I could lean it out some and took it for a long drive out in the countryside. Pulled the plugs and they look pretty good. There is a bit of a slight surge/hesitation at a light/moderate throttle so there is more to do but the car ran as good as it ever has in the short time that I’ve had it back on the road. I always attributed the earlier issues that I had when I was using my old carbs as being due to worn throttle shafts and that the fresh carbs would solve that. Now I know why the excessive jet depth was also present in my old carbs.

I can move on to something other than fiddling with my HS4’s. It’s been a frustrating experience since receiving my freshly rebuilt carbs. All my efforts to follow the manual to the letter resulted in having to turn the jets way down from the bridge and the front carb wanting more fuel vs. the rear carb. Countless jet depth checks, adjusting, driving, pulling plugs, etc. I decided to check where my old HS4’s were when I swapped in the fresh rebuilds. They too were way down which made me think about the common denominator which was the intake manifold. I cleaned the original one that came with my GT but didn’t check for flatness of the flanges so the plan today was to get the spare from my ‘70 parts and check it with the thought that I could resurface it and have it ready to swap over.

I’ve got some heavy granite tiles leftover from a project so I glued a sheet of 320 grit wet/dry paper to it and got every flange surface smooth and flat after removing the studs.Maybe a half hours worth of sanding. Removed all of the HS4 hardware from the GT, put some #2 Permatex on all of the gasket surfaces and buttoned everything back up. Went through the whole procedure, synched the carbs, mixture, idle, etc. , rechecked the timing and backed it off a bit, quick test drive and was pleasantly surprised at how it performed. I still feel as though I really had to lower the jets quite a bit but didn’t pull the dash pots. Didn’t have much gas in the tank and not much time either so there is more testing to do and analyzing plugs, and probably pull the dash pots to see where I wind up. Maybe the old girl just needs the jets lower than most of the other cars Inread about. Time will tell.

After a much needed camping trip on the Oregon coast, it was time to continue trying to get the newly rebuilt carbs dialed in. The new fuel filter that I ordered was waiting for me. Lots of particles in the old one so it was a good thing to change out. I’ve been fighting with the tuning as it seems like I’m having to run the jets down further than most from what I read which made me think something was amiss. Tore the carbs off and the intake manifold to check for anything that might be the cause of a leak. Ran the flanges over some sandpaper just to make sure the surface was dead flat. Did the same for the phenolic spacers, heat shield surfaces and then reassembled. Replaced one of the spacers as there was one edge that looked a little rough but other than that, no smoking gun was found. Pulled the plugs and cleaned, set the throttle disks 2 turns down from fully closed, 2 complete turns of the jets down from the bridge. Pulled the choke out and started, and warmed up the car. Only thing left to do was take it for a drive. As long as I had the choke out, it ran very nice which tells me I’m close but it’s still lean. A bit low on the gas gauge so back into the garage for the day. Dropped the jets another 2 flats and I’ll try again tomorrow.