BUILD THREAD GP403's sort-of-build thread
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So that terrible banging was just me having the clutch adjusted too far the wrong direction. I turned it back until it was grabbing, then backed it out just enough and that noise is gone. I guess it was so far out the return spring couldn't pull the throw out back far enough, so it was just banging around in there.
Pretty sure my overheating is indeed just a bad thermostat. The heater hoses and bypass tube on the water neck are hot, as is the top of the lower hose. Top hose and radiator are still cold. Sooooo.... off to the parts store and I'll hopefully report good news in a couple hours or so.
Pretty sure my overheating is indeed just a bad thermostat. The heater hoses and bypass tube on the water neck are hot, as is the top of the lower hose. Top hose and radiator are still cold. Sooooo.... off to the parts store and I'll hopefully report good news in a couple hours or so.
Good to hear. I had a bad Mr Gasket high flow thermostat. At idle it flowed fine, at speed it closed up. The lower rad hose and half the rad was cold. Tough to diagnose when you can feel flow through the top hose. Hopefully your water pump is a A/C closed impellar design. Although my Flowkooler high flow water pump never stopped my 403 from overheating. The Robert Shaw high flow thermostat works well but the good old Stant heavy duty thermostat is reliable.
At the risk of sounding like a complete moron, that banging noise had exactly f*ck all to do with the clutch. It was the #%&!#$% fan shroud hitting the top of the fan. WHY OH WHY it seemed to go away when I'd adjust the clutch I couldn't tell you. I went to adjust the clutch with the engine running and I'm underneath the car going "that noise is not coming from here....." Yeah. 
😵
Pull it up and tighten the bolts and whammo.
I did have a bad thermostat, got that swapped out and now I have a hot upper radiator hose, but my gage still keeps climbing. I shut it off at 3/4 because I'm being paranoid, but I don't think its right. Usually if you start overheating, you know it, the engine starts throwing off A LOT of heat. Not so much here. The cap side of the radiator is now slightly warm, but not ZOMG HOT like you'd expect an overheating engine to be. Also, I borrowed the wifey's laser thermometer from the kitchen, and the water neck/thermostat housing shows a nice calm ~179*. Which is about what I'd expect from a 180* thermostat and losing heat to the air.....
So, am I imagining things and maybe I got the wrong sending unit? Going to just buy another one to be sure. I won't be driving it down the road until I'm positive its not actually getting that hot.
Got a significant valve cover leak, too, but that's not a big deal.
😵 Pull it up and tighten the bolts and whammo.I did have a bad thermostat, got that swapped out and now I have a hot upper radiator hose, but my gage still keeps climbing. I shut it off at 3/4 because I'm being paranoid, but I don't think its right. Usually if you start overheating, you know it, the engine starts throwing off A LOT of heat. Not so much here. The cap side of the radiator is now slightly warm, but not ZOMG HOT like you'd expect an overheating engine to be. Also, I borrowed the wifey's laser thermometer from the kitchen, and the water neck/thermostat housing shows a nice calm ~179*. Which is about what I'd expect from a 180* thermostat and losing heat to the air.....
So, am I imagining things and maybe I got the wrong sending unit? Going to just buy another one to be sure. I won't be driving it down the road until I'm positive its not actually getting that hot.
Got a significant valve cover leak, too, but that's not a big deal.
Continued...
the best I can figure with that noise, is with the clutch out, the engine was physically loading up/down and torquing differently and slightly changing angles up and down....
the best I can figure with that noise, is with the clutch out, the engine was physically loading up/down and torquing differently and slightly changing angles up and down....
I have to say that the 'moment of truth' on an initial startup is always nerve racking for me. The little things keep me awake at night until I resolve them.
Congrats on getting it running. Little things are just that - little. And I use a heat gun during initial startup as well - never trust an untested gauge to ruin your new build.
Congrats on getting it running. Little things are just that - little. And I use a heat gun during initial startup as well - never trust an untested gauge to ruin your new build.
got the laser thermometer back out and used the Cutlass as a control. Sure enough, the readings were more or less the same. I think my heater control valve is stuck open on the GP tho. Meh whatever. I ordered a new sender to see if that cures it. It's the same kind, so maybe I have the wrong one in there. Figured they were basically the same thing since forever.
Saw a few intermittent bubbles in the return tank, but I'm hoping that was just bleeding going on. Burned off some exhaust paint and the exhaust smoke. So much water blowing out the tail pipes and the muffler clamp joints. Took her down the back roads a couple of miles and seemed to be OK. No more smoke when I got back, didn't see any more bubbles in the overflow either.
Time to clean up the shop and put the hood back on. Going to make a few short back-road runs before I go balls out 70mph/~3K RPM on the highway though just because.... As soon as that hood is back on you know something's going to happen. That's what this car does.
She needs cleaning up desperately. So much dust and spiders and clear coat issues from stuff sitting on it. I need to inspect these tires thoroughly, they were cheap POS's when I bought them in 2005(?) and it wouldn't surprise me if they're dry rotting. They're too tall anyway (225/70R14) and I don't like it. It'd be a waste because the tread is still great.
But damn it felt good running those gears even if I wasn't nailing it. That sound.
Also
and I probably just jinxed it.
Still need to get in the correct (I hope) fuel line and the choke heater tubes from inline. The fuel line right now is touching the thermostat and it gets hot. ++Valve cover gaskets and new sender.
Saw a few intermittent bubbles in the return tank, but I'm hoping that was just bleeding going on. Burned off some exhaust paint and the exhaust smoke. So much water blowing out the tail pipes and the muffler clamp joints. Took her down the back roads a couple of miles and seemed to be OK. No more smoke when I got back, didn't see any more bubbles in the overflow either.
Time to clean up the shop and put the hood back on. Going to make a few short back-road runs before I go balls out 70mph/~3K RPM on the highway though just because.... As soon as that hood is back on you know something's going to happen. That's what this car does.
She needs cleaning up desperately. So much dust and spiders and clear coat issues from stuff sitting on it. I need to inspect these tires thoroughly, they were cheap POS's when I bought them in 2005(?) and it wouldn't surprise me if they're dry rotting. They're too tall anyway (225/70R14) and I don't like it. It'd be a waste because the tread is still great.
But damn it felt good running those gears even if I wasn't nailing it. That sound.
Also
and I probably just jinxed it. Still need to get in the correct (I hope) fuel line and the choke heater tubes from inline. The fuel line right now is touching the thermostat and it gets hot. ++Valve cover gaskets and new sender.
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