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Tips
Tips

And so it begins again

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Tonight it was the clutch's turn. That actually took longer than the brakes. There was a LOT of air in the line. But, once it was done, the clutch felt really nice. Even though the hood is off, the car can now drive and stop. I also changed out the rear diff oil and succeeded in not making a huge mess for the first time. I guess the fourth time was the charm!

I still have a fair amount of work to go. I'm going one week on, one week off to keep myself from burning out on the repair work, working on bicycles and some aircraft parts during the interim.
 
Went to work replacing the leaking exhaust manifold gasket tonight. When I pulled the carbs, the fuel line which goes from one line to the other broke apart near the junction for the second float bowl. I just replaced that last year. Ugh. Really learning just how cheap the reproduction parts are. I'd have ordered a new one from AH Spares, but I'm trying to get the work finished up quickly and the shipping time from AH is a bit on the long side.

The manifold gasket had heaved out between cylinders 1 and 2 and it simply fell apart while I was removing it. New gasket when in and reattached the intake and exhaust manifolds. I found I was missing a gasket between the heat shield and the intake manifold, so had to order a new one of those, too. I have no idea what happened or where it disappeared to. I can't believe I would have put the car back together without one, but anything is possible. Will have to wait for fuel line and the gaskets to put the carb back on.
 
Continuing down the punch list, the water valve has been replaced and I swapped out the generator with a Chinese knock-off. I know with the Lucas generators, you want to keep the belt loose so you don't burn up the bearing. Do you do the same with the knock-offs? I ask because the knock off generator doesn't spin as freely as the Lucas one, so it would seem to need more belt tension to keep it moving. I can't tell until I get the carbs back on the car so I can start it.

Hopefully, I'll remain on track to have Baby Blue back on the road by March 1st.
 
Got the belt on correctly and the car fired up. I noticed a wet spot underneath one of the float bowls. Turns out the fuel line from the bottom of the float bowl to the carb is leaking. That's probably where my gasoline smell has been coming from all along. Was hoping to have the car done in time for some 60 degree weather predicted mid week, but that's no longer a possibility. Pics of the work coming soon.
 
Jet tube...try pushing it in and tightening the nut just a tad. Nothing to lose!
 
Tried the nut when I first found the leak - no joy, and actually seemed to make it worse. Before I yank the jet, I'm going to replace the washer and the rubber gland. The carbs were pretty well set up prior to the winter work, so I really am trying to avoid making large changes.

Looking at my pics, apparently this was there before I even pulled the carbs the in the first place.
 
Some photos...

Carbs off. I didn't realize I had the jet tube leak yet, but you can see the spilled gasoline on the lower left hand corner of the heat shield
DSC_1190 by David Cohen, on Flickr

Exhaust manifold -- you can see the way the gasket has heaved outwards just to the left of the left intake. That's now been fixed and the motor is a heck of a lot quieter now!
DSC_1192 by David Cohen, on Flickr

New water valve installed. It was identical to the one I got from VB. At least if this one leaks, I can take the old one and fix that and put it back one.
DSC_1196 by David Cohen, on Flickr

Carbs reinstalled:
DSC_1202 by David Cohen, on Flickr

New Generator installed. You can see the belt is "off the track" in this picture. Got that squared away today.
DSC_1203 by David Cohen, on Flickr

Garage door open and ready for a test run. Even with the carbs removed and put back on again, the Sprite fired up easily:
DSC_1204 by David Cohen, on Flickr

Gasoline leaking onto the heat shield. This has probably been going on for some time, and was probably the source of the gasoline smell I kept getting. It was hidden by the air cleaner.
DSC_1231 by David Cohen, on Flickr

All that's left on the checklist is the headlight harness upgrade, valve adjustments, leakdown & compression tests, new plugs, adjust the carbs, and give her a detailing top to bottom. Still shooting for having everything done before March 1st.
 
it may be leaking where the jet tube line attaches to the float bowl.
 
Trevor Jessie said:
it may be leaking where the jet tube line attaches to the float bowl.
Click to expand...

Yes, that is where the leak is. I'm thinking if I replace the washer and the rubber piece that will hopefully solve the problem. It certainly would explain why the engine was running so lean :wink-new:
 
those fittings are sort of fiddly. be sure you are working somewhere with good lighting so you can see any gunk left where the ring seats.
 
Pulled the plugs tonight. Thoughts of what you see?

DSC_0020 by David Cohen, on Flickr

All of them are oily to some extent with cylinders 1 & 2 getting the brunt of it. I'm not sure if the oil is coming up past the rings or dropping in through the valves. I think I may have missed on my valve adjustments last winter: I was watching for the valve to be in the "up" position rather than looking for the valve that was fully down and then using the "formula of 9" to figure out which one was in the up position, and I got the big puff of blue smoke after coasting down a hill and getting back into the gas again.

The tips have a lot of carbon on them. I've been running the carbs on the lean side and I don't think I can lean them out anymore without getting backfires, so I don't know what's exactly going on here.

Next steps are going to be a leakdown test and cold compression test, followed by a warm test.
 
Oily typically means rich not lean. Before you do anything put it all back together and take it for a good run - then check.

May be that the rings are getting tired but, you aren't racing it so, you are probably fine at least till next winter if you want to tear it down.
 
Ran both the leakdown and compression tests this evening on a cold engine:

2016 Leakdown results: 50% / 30% / 30% / 60%
2017 Leakdown results: 60% / 27% / 55% / 57%

I'm running the leakdown with the cylinder at its topmost travel. It is possible that I could be a little bit off causing the valves to open or close slightly

2016 Compression results: 165 / 162 / 165 / 180
2017 Compression results: 155 / 150 /135 / 150

I'll try hitting the compression again with a warm motor. My gut is telling me the 1275 is getting tired. I thought I could squeeze another two seasons out of the motor, but it is looking more likely I'm going to have to do something after this upcoming driving season.

As far as the rich / lean -- my gas mileage is telling me I'm running lean. I'm up around 28 to 30 mpg, which is higher than I had seen in previous seasons.
 
Replaced the rubber washer in the jet tube tonight. Had to pull the carbs again (this is now the 4th time) to do the job. The one that was in there had pretty much deteriorated and was likely the cause of the fuel leak. Put in a new set of plugs tonight. I just need to put the valve cover back on and all the mechanical stuff is done. I just need to install the new headlight harness, clean and detail the car and we'll be ready for another season of driving.
 
And after all that, the jet tube is still leaking. Looks like I'll need to replace the entire jet and pull the carb off for the 5th time. :mad-new:
 
SaxMan said:
And after all that, the jet tube is still leaking. Looks like I'll need to replace the entire jet and pull the carb off for the 5th time. :mad-new:
Click to expand...

Think of how good you are now at carb removal. :grin:
 
While you are at it... inspect the bowl for cracks.
 
Trevor Jessie said:
While you are at it... inspect the bowl for cracks.
Click to expand...

That was my next thought if replacing the jet doesn't work. I'm pretty certain it is the jet tube, though.

Finally had the "A Ha!" moment with the headlight harness. I was really overthinking it and now realize it's a pretty simple install.
 
Looked again tonight -- Jet Tube is actually split at the fitting, so hopefully the new jet will fix that problem.
 
Finished installing the headlight harness, and astonishingly, it worked on the first try. I tested them with the old headlights just in case something wasn't right. Even the old non-halogen headlamps were demonstrably brighter.

I ended up cutting holes in the headlight cups so the connectors could fit through. I'll patch the holes with electrical putty to make them water tight. It's not my prettiest installation, but fortunately most of the wiring will be hidden by the corrugated tube that runs along the right fender to the blower motor. I ran the wires over the top of the radiator shroud at the front. I discovered that old bicycle disc brake clips also make great wiring clips. Pics to come.
 
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