Do me a favor and torque them pressure plate bolts to spec.
Build Welcome home Matilda - faded like your favorite pair of jeans
- Thread starter CruiserTrash
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- Thread starter
- #462
Second guessing yourself now?
- Thread starter
- #463
I need help y’all. Another night, another attempt, but it still wants to die at idle. Here’s what I’m thinking:
Classic air/vacuum leak. Vacuum gauge readings are still dismal, wideband gauge is reading 17+ which is super lean. It’s sucking a massive amount of air from somewhere. Motor sounds healthier and doesn’t want to die at about 1200rpm and up, below that it tries to die. Vac gauge at 1200rpm (no load, not moving) is 7-8inHg, when here in Denver it should be at least 15. When I drive it down the block and the rpms are up, it drives great, feels really smooth and well balanced. At idle, for as crappy as it is, it doesn’t seem like there’s a miss.
-Carb and smog components were put on the new motor as they were on the old motor, which daily drove and had no issue idling or driving. EGR and Air Injection are removed as they were before. I removed the spaghetti hardline bundle with all of the vac lines and valves attached so I wouldn’t mess up replacing them. I am very familiar with these vac systems and can’t see anything wrong. Tonight I went over the Emissions FSM and checked my lines. That’s not to say I overlooked something.
-Did a smoke test and and carb cleaner spray test tonight looking for vac leaks. No adverse results from either.
-Tightened carb base nuts. The carb base is new.
-PCV valve and grommet are new.
-Timing is verified at 11* BTDC with HAC connected.
-Valves were set while hot yesterday.
*Could it be that on a “fresh” motor the carb needs a different tuning? So lean drop it all over again? Carb was rebuilt last winter and has provided months of perfect service.
*The cam is a NOS Toyota core with an RV grind by Delta. The core is for a 3F/E, which is advanced 4 degrees versus a stock 2F cam. Could that cause issues? I think from the mouth of some of the knowledgeable people on Mud I’ve read that won’t matter. Could the cam grind need different valve lash than stock? Would either of those things be enough to cause the truck to die at idle?
*I cleaned the manifold mating surface with red scotchbrite pads followed by brake cleaner wipes very well before installing with an OEM gasket. The head surface was machined flat when it was rebuilt. I ran out of time to check the bolt tightness on the manifolds tonight, but the idle didn’t surge when spraying all over them with carb cleaner. Could that still be an issue?
…So what do we think? I’m up for entertaining any wild theories at this point.
Classic air/vacuum leak. Vacuum gauge readings are still dismal, wideband gauge is reading 17+ which is super lean. It’s sucking a massive amount of air from somewhere. Motor sounds healthier and doesn’t want to die at about 1200rpm and up, below that it tries to die. Vac gauge at 1200rpm (no load, not moving) is 7-8inHg, when here in Denver it should be at least 15. When I drive it down the block and the rpms are up, it drives great, feels really smooth and well balanced. At idle, for as crappy as it is, it doesn’t seem like there’s a miss.
-Carb and smog components were put on the new motor as they were on the old motor, which daily drove and had no issue idling or driving. EGR and Air Injection are removed as they were before. I removed the spaghetti hardline bundle with all of the vac lines and valves attached so I wouldn’t mess up replacing them. I am very familiar with these vac systems and can’t see anything wrong. Tonight I went over the Emissions FSM and checked my lines. That’s not to say I overlooked something.
-Did a smoke test and and carb cleaner spray test tonight looking for vac leaks. No adverse results from either.
-Tightened carb base nuts. The carb base is new.
-PCV valve and grommet are new.
-Timing is verified at 11* BTDC with HAC connected.
-Valves were set while hot yesterday.
*Could it be that on a “fresh” motor the carb needs a different tuning? So lean drop it all over again? Carb was rebuilt last winter and has provided months of perfect service.
*The cam is a NOS Toyota core with an RV grind by Delta. The core is for a 3F/E, which is advanced 4 degrees versus a stock 2F cam. Could that cause issues? I think from the mouth of some of the knowledgeable people on Mud I’ve read that won’t matter. Could the cam grind need different valve lash than stock? Would either of those things be enough to cause the truck to die at idle?
*I cleaned the manifold mating surface with red scotchbrite pads followed by brake cleaner wipes very well before installing with an OEM gasket. The head surface was machined flat when it was rebuilt. I ran out of time to check the bolt tightness on the manifolds tonight, but the idle didn’t surge when spraying all over them with carb cleaner. Could that still be an issue?
…So what do we think? I’m up for entertaining any wild theories at this point.
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- Thread starter
- #465
Replaced two years ago with new. I’ll check it for cuts or nicks.
And yeah … it’s hard to diagnose anything without being right there. I think BVB will be visiting in the next couple days, but in the meantime I figured I’d make a post fishing for random tidbits and experiences.
Damn. There you go. Full stop. Wait for BVB. He’ll diagnose in 1.5 mins. No one on MUD is going to do what BVB can do. Ever.
I don’t think it would be a bad idea to tune the carb again.
- Thread starter
- #468
Crase came over to puzzle it out with me last night and is convinced a laying-on-of-hands (or exorcism) by BVB is all it needs.
My hope is that it’s something external to the long block. My deepest worry is that something internal to the long block is causing the problem. I did run it with the valve cover off two days ago and verified all the pushrods and rockers are moving, for example. I would think a stuck-open intake valve would wreck idle vacuum.
With as much due diligence as you afforded yourself it must be something simple like a vac line or you adjusted the carb backwards or something silly... If something went wrong internally with the cam break in you would most certainly have known it.
- Thread starter
- #470
talked with @RDub a little bit today and he cooked up some other ideas.
- bad brake booster would create a huge vacuum leak and both the smoke test and carb cleaner test wouldn't show that. Brake pressure feels normal though, and odds of it going bad by sitting for a week are low. It is 43 years old however.
- the hardline for the PCV hose at the intake has a very fat expanded ring on it to seal the rubber hose. I’ve noticed in the past that because of the manifold heat and because the hose gets very stretched out over that ring, cracks develop in that hose over the course of a year. I reused the PCV hose, so maybe that’s what’s happening. I could cut 1/2” off the end and jam it back on to solve the problem.
- I dug out my sheet from Delta Cam. It specs .014” for valve lash on both intake and exhaust. I set the valves to stock - the same .014 on exhaust, but a much tighter .008 for the intake. Perhaps the tighter valve lash is opening the intake valves too soon and leaving them open too late. Chances seem small, but there’s is a possibility that could cause a decrease in vacuum.
FYI, I found a chart here on Mud comparing cams, then edited it to show only the stock cam versus what I have.
With that additional amount and duration of intake valve lift, and the rocker hitting sooner than Delta prefers (due to my stock .008 clearance), it might just be causing me some issues. This gets into the stuff old hot rodders know, and that I absolute don't know at all. Those guys love a good lopey cam, which makes tuning for idle difficult and brings down idle vacuum but makes their car absolutely rip off idle. Obviously I don't want a lopey cam and lower idle vac, and I think in my conversations with Delta, this cam I have is not that at all. But with that intake lash misadjustment ... maybe it's having almost the same effect.
- bad brake booster would create a huge vacuum leak and both the smoke test and carb cleaner test wouldn't show that. Brake pressure feels normal though, and odds of it going bad by sitting for a week are low. It is 43 years old however.
- the hardline for the PCV hose at the intake has a very fat expanded ring on it to seal the rubber hose. I’ve noticed in the past that because of the manifold heat and because the hose gets very stretched out over that ring, cracks develop in that hose over the course of a year. I reused the PCV hose, so maybe that’s what’s happening. I could cut 1/2” off the end and jam it back on to solve the problem.
- I dug out my sheet from Delta Cam. It specs .014” for valve lash on both intake and exhaust. I set the valves to stock - the same .014 on exhaust, but a much tighter .008 for the intake. Perhaps the tighter valve lash is opening the intake valves too soon and leaving them open too late. Chances seem small, but there’s is a possibility that could cause a decrease in vacuum.
FYI, I found a chart here on Mud comparing cams, then edited it to show only the stock cam versus what I have.
With that additional amount and duration of intake valve lift, and the rocker hitting sooner than Delta prefers (due to my stock .008 clearance), it might just be causing me some issues. This gets into the stuff old hot rodders know, and that I absolute don't know at all. Those guys love a good lopey cam, which makes tuning for idle difficult and brings down idle vacuum but makes their car absolutely rip off idle. Obviously I don't want a lopey cam and lower idle vac, and I think in my conversations with Delta, this cam I have is not that at all. But with that intake lash misadjustment ... maybe it's having almost the same effect.
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That might do it. Should be an easy adjustment. But maybe have some fresh eyes on it first?
I may have missed it, but I don't see where you tested function of the ICS ?
- Thread starter
- #473
Working prior to engine disassembly! That was I think 11 days ago now. Just checked it again last night. Good thinking though.
And you're getting 12v to the harness side of connector Key On/ Engine off?
You're smog'd in Denver, yes? (I know it's L.A.s sister, politically).
You're smog'd in Denver, yes? (I know it's L.A.s sister, politically).
Only 7inHg is very low as you stated. . As a comparison, I get 19-20inHg at idle as sea level on my engine with ~5k on the clock. I would get it running at idle with the vacuum gauge hooked up and start by pinching off vacuum lines one by one to see if you can identify the leak that way. That should hopefully start eliminating some variables here.
Best of luck! You are super close and will get this sorted.
Cheers, James
Best of luck! You are super close and will get this sorted.
Cheers, James
- Thread starter
- #476
We got it. Had the legend BVB come lay hands on her. Couple things:
Yes, the valve lash being set to stock is NOT what this cam wants. Bill actually came in guessing intake valves, so we were both honing in on the same thing. Loosening up the intake valves helped greatly to at least get idle. But once we got there then we realized the new motor needed different things from the carb than the old motor wanted. I stood back and let him just tune it perfectly by ear.
Now that it idles and drives, a couple observations:
There’s some overlap in the cam and idle is going to be 8-10 here in Denver. It burbles nicely but is maybe more than I asked for, and I wonder how that low idle vac will do at high altitude. The balancing was 1000% worth it, it spins up so smooth. You almost don’t even feel the 2F under your right foot. How much “faster” it is than my old motor will come later, I need to put down some miles.
So now begins driving and further fine tuning. Maybe it wants more timing advance. Updates to follow.
@OGBeno BVB says hi
Yes, the valve lash being set to stock is NOT what this cam wants. Bill actually came in guessing intake valves, so we were both honing in on the same thing. Loosening up the intake valves helped greatly to at least get idle. But once we got there then we realized the new motor needed different things from the carb than the old motor wanted. I stood back and let him just tune it perfectly by ear.
Now that it idles and drives, a couple observations:
There’s some overlap in the cam and idle is going to be 8-10 here in Denver. It burbles nicely but is maybe more than I asked for, and I wonder how that low idle vac will do at high altitude. The balancing was 1000% worth it, it spins up so smooth. You almost don’t even feel the 2F under your right foot. How much “faster” it is than my old motor will come later, I need to put down some miles.
So now begins driving and further fine tuning. Maybe it wants more timing advance. Updates to follow.
@OGBeno BVB says hi
- Thread starter
- #477
- Thread starter
- #478
Anybody know how to read this balancing sheet?
Here is the cam sheet Delta sent me in case anyone is interested. I understand some of it, but not all.
Here is the cam sheet Delta sent me in case anyone is interested. I understand some of it, but not all.
- Thread starter
- #479
Just drove to work. Good lord does this motor like to spin. It feels like nothing for it to blow past 3000rpm. Super smooth. So far I feel a good bit of increased power between 1800 and about 2700 rpm. It also feels like there's some amount of power about 3000rpm, whereas on the old motor it didn't really feel like there was anything there at all.
The newly machined flywheel has changed the clutch adjustment so I need to get back underneath the truck and adjust the slave cylinder. My early truck needs 4-5mm of clearance between the pressure plate and TO bearing. The later trucks had the TO bearing resting on the pressure plate.
Brakes are a little squishier, but I think that was happening over time before the engine project anyway. Pads wearing down maybe. I need to at least inspect those prior to SAS.
Tomorrow or Sunday I'll try the intake valves at .016. I know there are drawbacks to too much or too little valve clearance, but I don't know if another 2 thou (or heck even another 4 thou) would be detrimental. More wear on the rocker faces? I also don't know how much idle vacuum and idle stability that will buy me. Currently it feels like the motor likes idling at about 900rpm. Below that it feels kind of lopey and burbly and the engine shakes just a little. It doesn't want to die, it just is that way down below about 850. Perhaps if I can add some valve clearance to the intake, increase the vacuum a touch, then I can bring down the idle speed just a little bit and have it be smooth. I'm also going to mess with timing a bit. Maybe the cam wants more initial advance.
The oil pressure gauge is much more responsive to current conditions. I think I used the sender that came with this core motor rather than the one that I was running before. It's an original Toyota sender. Before, the oil pressure would rest just below the 2/3 mark and never, ever move, not even by a fraction of a mm ... unless I was on the highway and then after about 5 minutes of cruising it would go to around 1/2 and stay there. This sender has my gauge coming down to 1/3 as soon as I come to a stop and idle. When I take off from a stop it jumps to 2/3, and it settles around half when cruising. All of those readings are ok (and I verified them with a secondary, accurate oil pressure gauge during the cam run-in, 2/3 is about 70psi), but I'm just pointing out that this sender makes the needle actually show things more accurately. Also, My old motor had the sender in one of the banjo fittings on the oil cooler, and this one is mounted into the oil filter bracket just below the filter. That could be the difference as well. That's also a good way to run two gauges - stock and an accurate aftermarket one. If you can find the proper banjo fitting that's threaded in the middle, you could pop another sender in there.
Temps are running great so far, although I just did a city drive and wasn't on the highway. dummy gauge is at about 3/5 and the Autometer gauge (upper radiator hose sender) is at 180-185. Thanks @yotadude520 for the Performance radiator. Performance is the brand, not an indicator that's it's special race tractor equipment. It's 4-row and brass, nuff said.
Zero leaks or drops so far. Last night I got under the truck and checked the oil pan arches and both are bone dry. If the front cover or rear main seal was leaking it would show up in those places too. That's not to say I won't encounter a leak as things settle in, but so far there's no hemorrhaging.
I'm pondering selling off some of the excess stuff I have from this project and offering some for free. I just have a ton of duplicates now. I'll likely keep the old long block in case something happens to this motor - I'd have a backup, especially of the head which is getting hard to find. But I have an extra oil pan, an extra flywheel that was machined last year. @HemiAlex supplied me with a pair of NOS timing gears so the used timing gears I took off would be offered for free - and they look great. I have extra radiator mounting brackets and motor mount brackets. Just a whole bunch of accumulated extras. If you're in need please reach out.
The newly machined flywheel has changed the clutch adjustment so I need to get back underneath the truck and adjust the slave cylinder. My early truck needs 4-5mm of clearance between the pressure plate and TO bearing. The later trucks had the TO bearing resting on the pressure plate.
Brakes are a little squishier, but I think that was happening over time before the engine project anyway. Pads wearing down maybe. I need to at least inspect those prior to SAS.
Tomorrow or Sunday I'll try the intake valves at .016. I know there are drawbacks to too much or too little valve clearance, but I don't know if another 2 thou (or heck even another 4 thou) would be detrimental. More wear on the rocker faces? I also don't know how much idle vacuum and idle stability that will buy me. Currently it feels like the motor likes idling at about 900rpm. Below that it feels kind of lopey and burbly and the engine shakes just a little. It doesn't want to die, it just is that way down below about 850. Perhaps if I can add some valve clearance to the intake, increase the vacuum a touch, then I can bring down the idle speed just a little bit and have it be smooth. I'm also going to mess with timing a bit. Maybe the cam wants more initial advance.
The oil pressure gauge is much more responsive to current conditions. I think I used the sender that came with this core motor rather than the one that I was running before. It's an original Toyota sender. Before, the oil pressure would rest just below the 2/3 mark and never, ever move, not even by a fraction of a mm ... unless I was on the highway and then after about 5 minutes of cruising it would go to around 1/2 and stay there. This sender has my gauge coming down to 1/3 as soon as I come to a stop and idle. When I take off from a stop it jumps to 2/3, and it settles around half when cruising. All of those readings are ok (and I verified them with a secondary, accurate oil pressure gauge during the cam run-in, 2/3 is about 70psi), but I'm just pointing out that this sender makes the needle actually show things more accurately. Also, My old motor had the sender in one of the banjo fittings on the oil cooler, and this one is mounted into the oil filter bracket just below the filter. That could be the difference as well. That's also a good way to run two gauges - stock and an accurate aftermarket one. If you can find the proper banjo fitting that's threaded in the middle, you could pop another sender in there.
Temps are running great so far, although I just did a city drive and wasn't on the highway. dummy gauge is at about 3/5 and the Autometer gauge (upper radiator hose sender) is at 180-185. Thanks @yotadude520 for the Performance radiator. Performance is the brand, not an indicator that's it's special race tractor equipment. It's 4-row and brass, nuff said.
Zero leaks or drops so far. Last night I got under the truck and checked the oil pan arches and both are bone dry. If the front cover or rear main seal was leaking it would show up in those places too. That's not to say I won't encounter a leak as things settle in, but so far there's no hemorrhaging.
I'm pondering selling off some of the excess stuff I have from this project and offering some for free. I just have a ton of duplicates now. I'll likely keep the old long block in case something happens to this motor - I'd have a backup, especially of the head which is getting hard to find. But I have an extra oil pan, an extra flywheel that was machined last year. @HemiAlex supplied me with a pair of NOS timing gears so the used timing gears I took off would be offered for free - and they look great. I have extra radiator mounting brackets and motor mount brackets. Just a whole bunch of accumulated extras. If you're in need please reach out.
If you have the space keep the block and head, you'll likely never need them but if you part with them then need a block or head in the future finding one will be difficult to impossible. If you have a space OEM carb keep that and have it rebuilt by a guru. Starter, distributor, coil and ignitor are other useful spares to retain, and the alternator.
I generally travel with a spare alternator and starter and have had to swap those parts out while traveling.
I generally travel with a spare alternator and starter and have had to swap those parts out while traveling.