1970 in CT (4 Viewers)

[ryanwk628]

My one hold up is that I replaced the manifold studs as the ones I had were abused and damaged. Dorman 675-359. These studs fit perfectly. Came in a box of 10. However now I can’t seem to get the exhaust manifold back on. May need to open a hole or two a bit

 

[ryanwk628]

Did some Dremel work to get the manifold over the new studs. I can see why the old ones were so mangled. Got it back together, made oil pressure and then running. Need to time it and burp the cooling system, then double check the valves and torques.

 

[ryanwk628]

Been cold out and the roads are salted so I haven’t been test driving it much, but heat cycled it a couple times, adjusted the valves, messed with the timing, idle mix and idle speed. Using my vac gauge it seems to like a bit more advance.

It has a very slight leak under from the rad drain extension so I need to sort that out. Hopefully dosent mean draining it again, but it was hot when I noticed so that can wait.

Need to dive back into the 4 speed and get that squared away, then the new tub can go on

 

[ryanwk628]

After a few heat cycles, re-torquing, and tuning idle mix, I was chasing a 14-15 Hg reading I realized I had a vacuum leak below the carb. Went to remove it, assuming it was the gasket, and turns out a PO's helicoil repair had failed.

I ordered a Big-sert from Time-Sert and repaired it in place.

It is slightly askew, maybe from the tape or the rake of the manifold relative to the carb mounting surface, but I took the stud out to install the isolator and slightly opened the carb hole. No leaks.

I am still confused however, because my vacuum gauge has been settling at a steady 15-16 in Hg at idle, when before the HEI dizzy, Fuji carb and head gasket I was getting ~20 in of Hg. Nothing changed in the bottom end. I cant find any more vacuum leaks and have checked my valves. It does go up to 20 after giving it gas, but settles back down in the red "lateing. timing" section. My distributor went back back where it was, even advanced it some more. My air cleaner is not on but I cant Imagine that would account for it. I did think it ran pretty well when I drove it around.

 

[ryanwk628]

My roof was in rough shape when I got it, and has not improved. It came with a bolted on roof rack that was drilled through the fiberglass. I had put screws and rubber washers through those holes, but was tired of looking at it. There were also a few gouges in the top from what I suspect were low objects.

At some point I want to redo the drip rail, but for the time being my goal was to plug the holes and get some paint on there. I looked at using marine-tex, or thickened epoxy, but as nothing was too big and that stuff is a bit thick, I went with epoxy fairing compound from total boat. It was thicker than I expected but got smooth the more I worked it. I filled the holes, cracks, and gouges, as well as built up the associated low spots.

This area had multiple holes drilled in it. I roughed them up and counter sunk them before packing with epoxy

This area looked like something dragged across the roof. The roof looks like it had primer and paint over gelcoat.

I did about 3 applications, sanding between each one. The amount of compound I purchased was more than enough.

Then I applied a 2k epoxy primer in beige which was a very close match to whatever color the roof was. I ended up seeing some areas that I thought warranted some more attention, sanded/filled them, and ordered a second can for more coverage. Sanded, dusted and preped between coats.

This is as it was drying in the garage. Some wet and some dry areas. The green filler sucked up the epoxy primer. I am going to put on some filler primer in a few areas before painting with color match paint I got a while ago. Not going crazy, Ill do that in the future when I address the rail, but its a big improvement over what it was.

 

[90WT]

Looking good. How did you find/order paint to match? Are you going original color, Shell Ivory?

 

[ryanwk628]

Looking good. How did you find/order paint to match? Are you going original color, Shell Ivory?

I have some Cygnus White, but now that you mentioned it I think Shell Ivory is the way I want to go. There is also a Ford color people have used that is close too. Its too cold to paint this week so Ill have time to do some more research

 

[ryanwk628]

Fired it up, cycled some gas through it. Fast idle is a bit high. Timing is not where I’d expect it to be, seems like it wants to be more advanced than it should, but that’s where it starts and runs…

Too much salt on the road so I decided to drive it through the woods.

 

[ryanwk628]

Since reinstalling the head, I have not driven it much, mostly just pulling it out and starting it once a month or so. It is parked at my step mother's and as the executor of my late father's estate I have a lot of clean out and house projects to do over there before she sells the place and this has consumed my weekends.

When I put it back together the DUI went right back in where it had been, I got it running and while it accelerates great, it just hasn't idled the way I wanted it too. The dizzy needed to be advanced more than it was when it came out. Checked the vacuum and it read low (12-15) and since it needed more advance to idle I was thinking lean condition. I really dug into it this weekend because I want it running right before I pull the gas tank and embark on this 3/4 tub project.

Purchased a better timing light, as the harbor freight "adjustable" one was a mile off for anything except 0 degrees advance. This new one has an integrated tach and it makes me wish I had done this sooner. This is what set me down this path, I wanted to set base timing at 12 per DUI recommendations and tune it right via the lean drop method.

12 degrees base timing lines up with where it was originally, I still have piece of painters tape I left on the firewall to indicate where it was when I pulled it before doing the head gasket. I got it to 12 degrees but then it didnt want to consistently idle below 900 with the timing there (vac advance pulled and capped.) I had to keep reving it to keep it going or it would bog and die. 1 1/2 turns out on the idle mix, 2, 2 1/2... nothing. Pulled the pin and blew carb cleaner in there, no noticiable change.

This is the Fuji carb I replaced the Chinese carb with. There was nothing especially wrong with the Chinese carb but I didnt trust it. I checked for vacuum leaks with carb cleaner and could not find any. Sprayed all over, no increase in RPMs. Retorqued all the manifold and carb base nuts anyway as it has heat cycled a few times. The Remflex and carb gaskets are all new. The isolator PCV system seems in good shape when I plugged one end and blew into it.

Checked the clearances valves, they were all slightly loose (~0.002ish) so I went through it again. No smoking guns, but I hoped that would solve it. It didnt.

Compression on all cylinders was around 145psi which I was thrilled with. Based on the compression and MLS gasket I replaced, I think this motor was rebuilt before the PO got it.

Plugs did not show much. 1 and 6 looked lean as one would expect with these manifold designs. 3 and 4 were darker but not awful. Most of the runs have just been monthly warm ups to not let it sit too long and gel up.

Still would not idle close to where I wanted it without advancing it a ton, so I could not do the lean drop tuning... pulled the carb.

 

[ryanwk628]

Fuel bowl level had been a bit low in the sight glass, near the top of the bottom tab. These were the out of the box settings. I since reset the float to 7.5mm using a stack of feeler gauges.

I watched all the pin head videos. At first I thought I would just take the throttle body off and find some debris or something... but there was nothing major. Blew it all out and flushed with carb cleaner. Then I tore the carb down and blew out all the passages. Carb cleaner seemed to move through fine. Cleared the jets with a bit of fishing line. Again, nothing obvious.

I checked the fuel cut off solenoid with an M12 battery and it clicks as it should. O ring looked fine. I pulled out the Chinese carb and tested that as well (pic below), both click.

Before reinstalling I checked the cut off wire in the engine bay, grounding the carb to the battery and the solenoid clicks when energized.

Now it is back on and when warm I can get it to idle, but the vacuum is still reading low. It is also inconsistent, one moment it is 700, then I rev it and it drops to 575, repeat and it does not come down the same way. But it was mostly averaging around 650 which is progress. Once warm it did idle without dying, but the gauge was still reading low.

I don't think the exhaust is causing back pressure, it seems to be flowing fine, though I intend to replace the muffler and need to make up a new tail pipe as that is too close for comfort with my gas tank plans.

The vacuum transfer case line is disconnected and capped. That worked as it should and capping it did not make a difference.

The readings when it idles in the spec rpm range are about 12-14 hg. When I rev it the vac drops to zero, then swings to 25, drops to about 17, then slowly drops towards the 12 as the revs come down. My thought so far has been something with the idle circuit, because of the idling issues and no other obvious loss of vacuum.

I ran out of time last night and needed to run home for parts. At this point my thoughts for next steps when I go back are:
- Swap the fuel cut off solenoid from the Chinese carb to the Fuji carb
- Swap the Chinese carb back on (need to swap back all the brackets I cannibalized for the Fuji)
- Maybe my vac gauge is bad?

 

[rlong]

Check thoroughly for vacuum leaks, both with carb cleaner... Use a hose with one end held up to your ear and the other to probe.. checking all logical and illogical places a vacuum leak could be.

 

[ryanwk628]

Swapped the carb back to the Chinese one. It seemed like it idled better (was set well before I swapped them) but still low vacuum which would drop off and would want to die without blipping the throttle.

The build quality on the Fuji is much better, but Im wondering if this has different jetting or something.

Check thoroughly for vacuum leaks, both with carb cleaner... Use a hose with one end held up to your ear and the other to probe.. checking all logical and illogical places a vacuum leak could be.

Its driving me crazy because I cant find anything. Retorqued the Remflex multiple times. I did not use sealer on it because everyone says not to, and I like the idea of not wasting the gasket if I have to remove it, but copper spray gasket is the next step. I think I will also open the holes on the manifolds to account for the new studs... they were difficult to fit so perhaps they are binding up on the studs and not fully seating against the head?

I started down this rabbit hole because I wanted to make sure it was running right before I pull the gas tank for the 3/4 tub swap. Once I get this sorted, the Sawzall is coming out. Lots of weight reduction behind the POs riveted on diamond plate

 

[90WT]

Did you check the PCV valve is working correctly? Also vacuum lines for brake booster? (Edit: looks like you don't have a booster)
And are you connecting your vacuum gage near the carb base, not from the port running to the distributor?
If everything checks out, might have to pull the intake/exhaust gasket and inspect/replace. Sometimes I can't tell if it's bad unless I pull it off and can see the discoloration. I don't use any gasket sealer on that one, so I kinda figure it's a one and done gasket. Any time I mess with it, I change it out. I've used a couple of Remflex ones, and recently got one from Napa that seems to be working great.

 

[ryanwk628]

Did you check the PCV valve is working correctly? Also vacuum lines for brake booster? (Edit: looks like you don't have a booster)
And are you connecting your vacuum gage near the carb base, not from the port running to the distributor?
If everything checks out, might have to pull the intake/exhaust gasket and inspect/replace. Sometimes I can't tell if it's bad unless I pull it off and can see the discoloration. I don't use any gasket sealer on that one, so I kinda figure it's a one and done gasket. Any time I mess with it, I change it out. I've used a couple of Remflex ones, and recently got one from Napa that seems to be working great.

I have a barb I tapped into the manifold as a test port.

Should have mentioned I thought of that last night and checked the PCV, it seems to be working. The hose holds pressure when I plug one end and blow in the other. The valve rattles, and seems to work.

I thought perhaps it was an issue with the vac shift T/C, but I pulled and capped that port.

Process of elimination, it must be the gasket (right?) Its a Remflex without sealer, but at this point Im thinking sealer may be needed for any imperfections

 

[90WT]

When I fiddled with my carb, I was able to get maybe 1 inch of mercury, not a huge gain. And that's what makes me suspect your intake/exhaust gasket. What was your best baseline vacuum reading? 18-20 inches?

For me, as much as I've tried to tuck the exhaust pipe up above the frame, I still hit that sucker when offroading. Hitting the pipe puts a torque on the intake/exhaust manifold causing it to not seal correctly against the head. Tightening the manifolds doesn't help when you tweak the gasket, so I've replaced the gasket at least 4 times in 4 years. I change it out more than I change the oil or spark plugs. That gain in vacuum, even for a small leak at the gasket, in more like 3-5 inches.

You may already do this, but when you install the intake/exhaust manifold , be sure to tighten them against the head, and then to each other. The seal at the head is more important.

 

[ryanwk628]

When I fiddled with my carb, I was able to get maybe 1 inch of mercury, not a huge gain. And that's what makes me suspect your intake/exhaust gasket. What was your best baseline vacuum reading? 18-20 inches?

For me, as much as I've tried to tuck the exhaust pipe up above the frame, I still hit that sucker when offroading. Hitting the pipe puts a torque on the intake/exhaust manifold causing it to not seal correctly against the head. Tightening the manifolds doesn't help when you tweak the gasket, so I've replaced the gasket at least 4 times in 4 years. I change it out more than I change the oil or spark plugs. That gain in vacuum, even for a small leak at the gasket, in more like 3-5 inches.

You may already do this, but when you install the intake/exhaust manifold , be sure to tighten them against the head, and then to each other. The seal at the head is more important.

All good tips, thank you! Loosening the manifolds is a good one. Ill feel silly if this solves it, but will be glad if it does.

 

[ryanwk628]

Remflex gasket had a big split around the cyl 4 stud. It came apart when I took it off which was disappointing too. Brand new and wasn’t cheap. Also frustrating I chased so many other things.

I can get a Felpro gasket this week. Fingers crossed

 

[ryanwk628]

Well now after waiting 24 hours I have an exhaust leak too. 4 & 5.

Bent gasket out of the box didn’t inspire confidence

Don’t love the fit, lots of the metal sealing surface hangs out rather than sealing

And my manifold vac is still reading low.

Can’t mess with it now. Need to go do chores. I guess I’ll pull it off again and goop it up with more permatex? I’m going to find another gauge to confirm vac.

So much for sorting this and pulling the tank this weekend

 

[charliemeyer007]

+1 for find a second gauge. The seller/packer owes you a new gasket IMHO for poor packing.

 

[ryanwk628]

+1 for find a second gauge. The seller/packer owes you a new gasket IMHO for poor packing.

Used carb cleaner and found the felpro also has an intake leak on 3&4 so it was a trick to find an idle. This thing just does not line up well with my manifolds.

Still, in spite of that the new vacuum gauge put me into the green (at ~850 rpm and a lot of idle mix.)

Same conditions, (compensating for the gasket leak)

New Remflex will be going in this weekend. Then I will work on tuning it as I originally intended.

I do think there was an issue with the carb idle circuit because it idled much better with normal DUI timing after I took it apart and cleaned it. However the faulty gauge readings sent me down a rabbit hole.

Oh well, at least I figured something out tonight!