Project Resurrection: Running Log
05-23-12, 09:48 AM
#526
i don't know about the TR, but i DO know about the cat. i put an EGT sensor on the vert for a day, and the exhaust gasses never went over 720c, idle is 450-500c. the actual cat itself supposedly runs in the 500-700c range, and i'd expect the TR to be in that ballpark.
of course that's INSIDE, so what the outside temp is, is hard to say...
of course that's INSIDE, so what the outside temp is, is hard to say...
The inner and outer jackets of the TR are separated by an air chamber that gets air from the air pump pushed through it (via the ACV) under certain engine conditions. The same airflow cools the first bend of the "air duct" (downpipe)... which is the high failure point on that now-hard-to-find part.
Seems like a common failure of smog equipment on SA's goes something like:
1) ACV or it's controlling solenoid goes bad
---or---
1) TR inside jacket gets a crack in it from a vicious afterburn
2) Cooling air no longer goes thru the TR in sufficient quantity, or hot exhaust leaks in there
3) TR and air duct overheat
4) Weld on first joint of the air duct literally boils away; seal on secondary air path is lost
5) Air flow from the heat exchanger into the secondary air ports is compromised
6) Emissions fail
I worry about such things because I'm getting damn tired of having to scrounge up smog parts that haven't been made in 20 years just to be allowed to keep driving my car.
I don't have much of a sense of humor about it any more, I gotta admit.
05-24-12, 12:06 AM
#527
Did an 'extended idle' warmup in the garage, including 5 mins at 2000 rpm unloaded.
The IR thermometer is a fun little toy; got it off newegg for less than $40 and I'm learning interesting things with it already.
The TR outer casing rear at the block junction (hottest spot visible with heat sheilds in place) clears 450deg after an extended idle. The front face where cooling air goes in doesn't even make 300. my 500-deg paint just wont cut it for the top heat sheild, though the sides are fine.
I verified where on my stock temp guage the needle reads when the sensor is actually at 180 deg. Also verified accuracy of my oil temp gauge by measuring the temp of the fitting.
exhaust gasses leaving the rear of the muffler hit 450 even during extended idle.
I can measure temps at the water pump and verify the opening temp of the switch easily. I can also see radiator inflow and outflow temps, likewise for the oil cooler.
I also think I've verified that my 'collant bubbles' are actually a slightly wonky lead on the coolant level sensor, which is a relief.
The IR thermometer is a fun little toy; got it off newegg for less than $40 and I'm learning interesting things with it already.
The TR outer casing rear at the block junction (hottest spot visible with heat sheilds in place) clears 450deg after an extended idle. The front face where cooling air goes in doesn't even make 300. my 500-deg paint just wont cut it for the top heat sheild, though the sides are fine.
I verified where on my stock temp guage the needle reads when the sensor is actually at 180 deg. Also verified accuracy of my oil temp gauge by measuring the temp of the fitting.
exhaust gasses leaving the rear of the muffler hit 450 even during extended idle.
I can measure temps at the water pump and verify the opening temp of the switch easily. I can also see radiator inflow and outflow temps, likewise for the oil cooler.
I also think I've verified that my 'collant bubbles' are actually a slightly wonky lead on the coolant level sensor, which is a relief.
05-24-12, 10:25 AM
#528
Rear bowl levels continue to rise ~30 mins after shutdown, and then later fall over several hours, but the limits are not as extreme as they were before my rebuild, and I don't seem to experience any significant engine flooding as a result. Restarts remain essentially smoke free and I don't get the horrid choking one-rotor-running restarts that I was seeing before the tear-down.
Previously, the rear bowl level would rise to completely fill the bowl (no air visible in the sight glass). Post-rebuild, the level still rises, but only about 1/2 to 2/3 of the distance from the 'normal' mark to the top of the window; at peak there is still substantial air space visible.
At the lowest, which occurs several hours after shutdown, the level in the bowl seems about equal to the bottom of the window.
The front bowl level also rises and falls, but not nearly as much - - it goes up maybe 15% above normal, and then drops to about 5% below normal several hours later.
If it's not flooding the engine, and thus not putting me at risk for excessive wear, it's "good enough" but it's still a puzzle I want to solve. Somehow.
Previously, the rear bowl level would rise to completely fill the bowl (no air visible in the sight glass). Post-rebuild, the level still rises, but only about 1/2 to 2/3 of the distance from the 'normal' mark to the top of the window; at peak there is still substantial air space visible.
At the lowest, which occurs several hours after shutdown, the level in the bowl seems about equal to the bottom of the window.
The front bowl level also rises and falls, but not nearly as much - - it goes up maybe 15% above normal, and then drops to about 5% below normal several hours later.
If it's not flooding the engine, and thus not putting me at risk for excessive wear, it's "good enough" but it's still a puzzle I want to solve. Somehow.
05-24-12, 11:05 AM
#531
Pretty much; this weekend I'm going to walk through the FSM emissions tests, make sure everything is cycling at the right time. I've got the time, so I'm gonna do the diligence.
I thought I might have a block coolant leak that was causing a rad bubble (!), but it seems like it's just a flaky level sensor - - goes away when I wiggle the connection.
Wish I could, but I'm a carb guy deep down. I just wish I could simplify the Nikki so it could deliver on its potential.
Thanks; I'll need the luck since there's really no way to know if it'll pass. 
I thought I might have a block coolant leak that was causing a rad bubble (!), but it seems like it's just a flaky level sensor - - goes away when I wiggle the connection.
Wish I could, but I'm a carb guy deep down. I just wish I could simplify the Nikki so it could deliver on its potential.
05-31-12, 10:38 AM
#532
More data, don't know what it means yet: The bowl levels absolutely track bowl temperature; using the IR thermometer & sampling every 5 minutes after shutdown, I can watch bowl temps rise as the loss of normal carb cooling from fresh gas and airflow/expansion stops, and the carb starts to heat soak.
Normal bowl temps at shudown in the evenings here has been about 80deg.
As exterior bowl temps rise above about 90f, the rear bowl fuel level starts to visibly rise. When the bowl temps peak around 115 or so, the fuel level has peaked. As temps fall, the levels drop. Effect is much more pronounced on the rear bowl, but you can detect the rise and fall in the front bowl, too. It's just less.
The coefficient of thermal expansion of gasoline is 0.000950/per degree. A 35-deg rise in temp should then result in just under a 3.5% increase in volume. Doesn't seem enough to account for what I've been seeing, but the shape of the bowl with the float down in in it makes this hard to judge. The rear bowl does have a larger effective volume, due to the fuel-filled passages for the AP and the richer that are attached to it. Which means the vertical rise of the level would be more.
The boiling point (vaporization temperature) of gasoline may figure into this too, but that's a number almost impossible to lock down - - engineering references say it can vary from 100 to 400 deg F depending on the specific formula, the octane rating, and additives involved.
Normal bowl temps at shudown in the evenings here has been about 80deg.
As exterior bowl temps rise above about 90f, the rear bowl fuel level starts to visibly rise. When the bowl temps peak around 115 or so, the fuel level has peaked. As temps fall, the levels drop. Effect is much more pronounced on the rear bowl, but you can detect the rise and fall in the front bowl, too. It's just less.
The coefficient of thermal expansion of gasoline is 0.000950/per degree. A 35-deg rise in temp should then result in just under a 3.5% increase in volume. Doesn't seem enough to account for what I've been seeing, but the shape of the bowl with the float down in in it makes this hard to judge. The rear bowl does have a larger effective volume, due to the fuel-filled passages for the AP and the richer that are attached to it. Which means the vertical rise of the level would be more.
The boiling point (vaporization temperature) of gasoline may figure into this too, but that's a number almost impossible to lock down - - engineering references say it can vary from 100 to 400 deg F depending on the specific formula, the octane rating, and additives involved.
06-01-12, 11:48 PM
#535
I finished assembling the new (spare) dizzy, and set the timing. I shot some video before I readjusted the idle, so I could have a true "apples^2" comparison.
The original dizzy had quite a bit of end-play compared to the new one.
Explanatory note: our distributors have two separate shaft segments in them; the 1) bottom section which engages the e-shaft gear and rides on the housing bushings, and which also carries the bottom part of the mechanical advance mechanism,and the 2) upper section which fits over the top end of the bottom shaft, carries the reluctor wheel, and engages the top half of the mech advance.
Because the shaft is split in the middle, there can be end play in both parts.
End play in the bottom part would be more likely to mess with timing (seems to me) since letting the shaft move in and out would change the engagement point of the helical drive gears. End play in the top half wouldn't matter as much to timing, since the reluctor is straight-cut. Moving it vertically wouldn't effect timing.
Original dizzy had bottom-half end play of 18 thousandths, and top half play of 12 thousandths (0.018" & 0.012")
The freshly-rebuilt replacement ('new') dizzy had bottom play of only 5 thousandths, and top play of 18 thousandths (0.005" & 0.018")
Before and after videos:
Original Dizzy
Freshly refurb'ed 'Spare' Dizzy (newer camera, which sucks on audio and noise, frankly)
Seems to me that the replacement dizzy eliminated a lot of the 'impact' of the miss; you can still hear it just slightly, and see it if you look close, but it's much weaker - - it doesn't shake the engine nearly as much.
My theory is that the slop in the bottom end of the original dizzy allowed the timing to get 'tossed ahead' when the miss happens, making the next firing a bit off-time and contributing to the strength of the miss.
Looking at the timing marks with a timing light, I can say that the timing is visibly more stable with the tighter dizzy. It used to jitter a bit visibly, but now it looks rock-steady.
Bottom line is: replacing the dizzy greatly reduced the severity of the miss, to the point where it is barely noticeable now at idle.
It should be possible to tighten up end-play on a dizzy, since between the housing and the drive gear there is a hardened spacing washer. If a thicker washer of the proper ID/OD could be had, it would remove end play in the bottom half.
There's a load washer at the top too, but it is below a drive-in grease seal, and could only be changed by removing and replacing the seal.
The original dizzy had quite a bit of end-play compared to the new one.
Explanatory note: our distributors have two separate shaft segments in them; the 1) bottom section which engages the e-shaft gear and rides on the housing bushings, and which also carries the bottom part of the mechanical advance mechanism,and the 2) upper section which fits over the top end of the bottom shaft, carries the reluctor wheel, and engages the top half of the mech advance.
Because the shaft is split in the middle, there can be end play in both parts.
End play in the bottom part would be more likely to mess with timing (seems to me) since letting the shaft move in and out would change the engagement point of the helical drive gears. End play in the top half wouldn't matter as much to timing, since the reluctor is straight-cut. Moving it vertically wouldn't effect timing.
Original dizzy had bottom-half end play of 18 thousandths, and top half play of 12 thousandths (0.018" & 0.012")
The freshly-rebuilt replacement ('new') dizzy had bottom play of only 5 thousandths, and top play of 18 thousandths (0.005" & 0.018")
Before and after videos:
Original Dizzy
Freshly refurb'ed 'Spare' Dizzy (newer camera, which sucks on audio and noise, frankly)
Seems to me that the replacement dizzy eliminated a lot of the 'impact' of the miss; you can still hear it just slightly, and see it if you look close, but it's much weaker - - it doesn't shake the engine nearly as much.
My theory is that the slop in the bottom end of the original dizzy allowed the timing to get 'tossed ahead' when the miss happens, making the next firing a bit off-time and contributing to the strength of the miss.
Looking at the timing marks with a timing light, I can say that the timing is visibly more stable with the tighter dizzy. It used to jitter a bit visibly, but now it looks rock-steady.
Bottom line is: replacing the dizzy greatly reduced the severity of the miss, to the point where it is barely noticeable now at idle.
It should be possible to tighten up end-play on a dizzy, since between the housing and the drive gear there is a hardened spacing washer. If a thicker washer of the proper ID/OD could be had, it would remove end play in the bottom half.
There's a load washer at the top too, but it is below a drive-in grease seal, and could only be changed by removing and replacing the seal.
06-02-12, 03:21 PM
#536
Day 1323
I heartily and profoundly request the Calfironia Air Resources Board take a copy of all their regulations, fold them until they consist of nothing but a collection of sharp corners, and stuff them up their collective green fogholes.
Take that, you bastards! You missed me again!
I've jumped through their flaming hoops for 23 years now. Still rolling.
I heartily and profoundly request the Calfironia Air Resources Board take a copy of all their regulations, fold them until they consist of nothing but a collection of sharp corners, and stuff them up their collective green fogholes.
Take that, you bastards! You missed me again!
I've jumped through their flaming hoops for 23 years now. Still rolling.
06-02-12, 10:35 PM
#538
Sin City Rotary
Day 1323
I heartily and profoundly request the Calfironia Air Resources Board take a copy of all their regulations, fold them until they consist of nothing but a collection of sharp corners, and stuff them up their collective green fogholes.
Take that, you bastards! You missed me again!
I've jumped through their flaming hoops for 23 years now. Still rolling.
I heartily and profoundly request the Calfironia Air Resources Board take a copy of all their regulations, fold them until they consist of nothing but a collection of sharp corners, and stuff them up their collective green fogholes.
Take that, you bastards! You missed me again!
I've jumped through their flaming hoops for 23 years now. Still rolling.
06-03-12, 04:28 PM
#539
The hot-shutdown flood is rearing it's head again - - but I have to drive the car a more substantial amount of time for it to happen.
I'm beginning to suspect that it's in part due to the reformulated Cali gasolines having a much lower boiling point (more volatile) than the fuel these cars were designed for, and in part because my TR gets hotter than it should.
It's clearly related to carb temps in some way.
I'm beginning to suspect that it's in part due to the reformulated Cali gasolines having a much lower boiling point (more volatile) than the fuel these cars were designed for, and in part because my TR gets hotter than it should.
It's clearly related to carb temps in some way.
06-04-12, 12:41 PM
#541
Yah, it's making me crazy. It's gotta be heat related since it only happens after a good long run, and the rising fuel levels directly follow rising carb bowl temps after shutdown.
That, and I've literally eliminated pretty much every other possible cause.
Only parts of the vent/vapor system that have not been replaced is the charcoal canister in the air cleaner lid, and the vent control valve... and both test as good per FSM test procedures.
I'm tempted to gimmick the vent system to 'always open' just to eliminate it once and for all, now that I'm smog-test-free for almost two years. But dammit, it... should... work... as... designed!
Or to build a modded carb with old-style open balance tubes.
That, and I've literally eliminated pretty much every other possible cause.
Only parts of the vent/vapor system that have not been replaced is the charcoal canister in the air cleaner lid, and the vent control valve... and both test as good per FSM test procedures.
I'm tempted to gimmick the vent system to 'always open' just to eliminate it once and for all, now that I'm smog-test-free for almost two years. But dammit, it... should... work... as... designed!
Or to build a modded carb with old-style open balance tubes.
06-09-12, 01:34 PM
#542
A lot of the classic-car web sites are full of posts about carbureted old-schoolers having trouble with 10%-ethanol gas and after-stop flooding. Also attributed to fuel boiling.
They also run into high instances of vapor lock for the same reasons - - older motors used in-engine diaphragm fuel pumps. Engine-heated fuel would vaporize in the lines, causing the pumps to cavitate & lose the ability to pump fuel. Vapor lock was the main reason electric fuel pumps became the norm.
I may be fighting a basic incompatibility between ethanol-bearing gas (especially in 'winter' formulas here in Cali, which are intentionally high-volatile) and the stock Thermal Reactor design.
If true, there's irony for you; the state-mandated emissions controls being incompatible with the state-mandated clean-burning gas.
Maybe I need a system that pumps bowl fuel back into the tank after shutdown... Would be illegal to do in Cali, though, as I'd be modifying the emissions system.
They also run into high instances of vapor lock for the same reasons - - older motors used in-engine diaphragm fuel pumps. Engine-heated fuel would vaporize in the lines, causing the pumps to cavitate & lose the ability to pump fuel. Vapor lock was the main reason electric fuel pumps became the norm.
I may be fighting a basic incompatibility between ethanol-bearing gas (especially in 'winter' formulas here in Cali, which are intentionally high-volatile) and the stock Thermal Reactor design.
If true, there's irony for you; the state-mandated emissions controls being incompatible with the state-mandated clean-burning gas.
Maybe I need a system that pumps bowl fuel back into the tank after shutdown... Would be illegal to do in Cali, though, as I'd be modifying the emissions system.
06-09-12, 02:04 PM
#543
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the other thing the E10 does is act "leaner", gasoline has a stoichiometry point of 14.7:1, while E10 is more like 14.2:1, so on a carbed car, you'll be a tad leaner.
there actually is gasoline around that ISN'T E10, racetracks and airports all use regular fuel
*the TDI VW i think was the lone exception.
07-01-12, 02:02 PM
#546
Day 1342
Changed out my engine-build oil and filter - nothing unexpected came out, which is good - and took the car for a long, hot drive with my alternate air-cleaner cover/carbon canister installed. Nearly an hour of stop-and-go surface traffic followed by a 10-min freeway run at 4k (5th gear) & into the barn, then let it sop up the 90-degree heat.
90 minutes later, I went to start it. The engine was still hot enough that the choke would not stay pulled (so, block water temp above 180)... and I encountered a mild semi-flood condition. I had to hold the pedal flat and crank for about 8-10 seconds before she lit off, and blew a smallish amount of black smoke. It then took about 20 seconds of part-throttle runningbefore she would idle smoothly & stop 'clearing her throat'.
This is far improved from what I experienced a week ago, using my older air cleaner cover/ carbon canister. All other conditions virtually identical, but that time she was harder to start, blew a hell of a lot more (black) smoke, and took about a minute or more to settle doewn to a good idle.
Which means the hot-shutdown flood is definitely related to the condition/age of the carbon canister's filling, that being the only thng I changed.
Now, even my 'newest' air-cleaner cover is not young; it's the original one from my car, which was swapped out of use in 08 for the used one I bought and prettified.
I'm willing to invest some time and effort on the premise that I can pretty much eliminate this post-shutdown flood if the carbon filler is in adequately good condition, even with the high-volatile gas being used today in CA.
So, I got another used air-cleaner cover off e-bay, and I'm going to disassemble it, find proper new activated carbon filler, and work out a way to make the canister 'serviceable' instead of just replaceable. It's all spot-welded together so some drilling and brazing is probably called for.
Changed out my engine-build oil and filter - nothing unexpected came out, which is good - and took the car for a long, hot drive with my alternate air-cleaner cover/carbon canister installed. Nearly an hour of stop-and-go surface traffic followed by a 10-min freeway run at 4k (5th gear) & into the barn, then let it sop up the 90-degree heat.
90 minutes later, I went to start it. The engine was still hot enough that the choke would not stay pulled (so, block water temp above 180)... and I encountered a mild semi-flood condition. I had to hold the pedal flat and crank for about 8-10 seconds before she lit off, and blew a smallish amount of black smoke. It then took about 20 seconds of part-throttle runningbefore she would idle smoothly & stop 'clearing her throat'.
This is far improved from what I experienced a week ago, using my older air cleaner cover/ carbon canister. All other conditions virtually identical, but that time she was harder to start, blew a hell of a lot more (black) smoke, and took about a minute or more to settle doewn to a good idle.
Which means the hot-shutdown flood is definitely related to the condition/age of the carbon canister's filling, that being the only thng I changed.
Now, even my 'newest' air-cleaner cover is not young; it's the original one from my car, which was swapped out of use in 08 for the used one I bought and prettified.
I'm willing to invest some time and effort on the premise that I can pretty much eliminate this post-shutdown flood if the carbon filler is in adequately good condition, even with the high-volatile gas being used today in CA.
So, I got another used air-cleaner cover off e-bay, and I'm going to disassemble it, find proper new activated carbon filler, and work out a way to make the canister 'serviceable' instead of just replaceable. It's all spot-welded together so some drilling and brazing is probably called for.
07-03-12, 07:24 AM
#547
It's been a long time since I looked at a SA air box, but I'm wondering if, after you drill out the spot welds, you could then weld some studs onto the lid itself and use lock nuts or something to hold the canister piece on. That way it'd look stock from the outside and easily removed to service.
I've never really looked into it, but can you buy the stuff in those canisters easily/readily??
I've never really looked into it, but can you buy the stuff in those canisters easily/readily??
07-03-12, 09:51 AM
#548
I don't understand how you guy's can let some government official violate your auto like that. It would give me the creeps. 
Why don't you just have a PO box in a state that doesn't do emissions checks and have tags/licence from that state as well?
Why don't you just have a PO box in a state that doesn't do emissions checks and have tags/licence from that state as well?
07-03-12, 04:38 PM
#549
It's been a long time since I looked at a SA air box, but I'm wondering if, after you drill out the spot welds, you could then weld some studs onto the lid itself and use lock nuts or something to hold the canister piece on. That way it'd look stock from the outside and easily removed to service.
I've never really looked into it, but can you buy the stuff in those canisters easily/readily??
I've never really looked into it, but can you buy the stuff in those canisters easily/readily??
I got way too much to lose to play that game... especially when I'm still able to beat them at theirs.
07-05-12, 08:02 AM
#550
^I'll be interested to see what you come up with on that lid.
I agree - too much at risk just to get a car through inspection. People have tried (and usually failed) to use all those tricks around here too, in the end it always catches up to them. Much easier to just leave the emissions stuff on there and be done with it...
I agree - too much at risk just to get a car through inspection. People have tried (and usually failed) to use all those tricks around here too, in the end it always catches up to them. Much easier to just leave the emissions stuff on there and be done with it...