Latest Installment - New Build 445 Problems.

[Yellow Truck]

So a short recap - I previously posted some videos of my 445 running pretty roughly and described some other issues including hard starting, poor power, and low vacuum. I also mentioned that I had a loud whistle coming from the carb.

Howie (ScotiaFE), who hasn't been around in a while, suggested my main problem was I was hanging valves. I re-did the lifter pre-load following Barry's advice - turned down the adjustment screw until it made contact with the pushrod, and then one more full turn. This made a difference and I saw vacuum come up to about 10 inches, it started easier and ran smoother, and seemed to have a lot more power.

In addition I took off the carb and adjusted the rear butterfly to close it a little more - this eliminated the whistle, and I adjusted the idle mixture a little. Without going any deeper I stopped there with the carb but I did check the timing and turned it up to about 16 degrees of advance and it ran most happily there.

At this point I took it in to have new collectors made and new headers installed to stop all the exhaust leaks, and when I dropped it off I had to move it and on the warm restart I had a kickback on the starter suggesting it was too far advanced. I got it back this morning with the new headers.

The exhaust shop is also a bit of a local hotrod garage and the owner and his mechanic are well respected in the hobby locally. His experience with FEs is not great, but he has worked on some. He told me that he was pretty sure I had a miss when it was cold (popping though the exhaust and running very rough) that went away as it warmed up. He said it sounded to him like I was still tight on the valves. I told him how the pre-load was set and he was surprised - his experience with the other team suggested 1/2 turn of pre-load after contact with the pushrod.

We discussed setting it up and he told me to check the exhaust temperatures on the pipes when I got home, and the temperature range I was looking for would be between 325 and 375, particularly on the rear pipes, possibly a little lower on the front ones. I drove it home (about 15 minutes) and noted that it was not running as well as the morning I took it in a week ago. In particular in 3rd (really 2nd since you start it in 2nd) it was balky and choppy at low RPM after the shift.

The results were surprising - my pipes at idle with a motor that had run for 20 minutes were (in degrees F):

• 1 - 270 / 5 -420
• 2 - 475 / 6 - 475
• 3 - 430 / 7 - 275
• 4 - 315 / 8 - 215

I checked it a couple of times and the numbers bounce around a bit but they were consistent enough. I also checked the timing to reduce the advance and to my surprise it was not at the 18 I set it at but was now up around 28 degrees. I went to take the vacuum advance hose off and it was already off - it is usually connected to the timed port on the side of the QFT. I backed the timing down to about 16 degrees advance, and checked the vacuum. It was at around 5 inches at 28 degrees and came up to about 8 at 16 degrees. A few weeks ago it had been up around 10 inches, since the last time I checked the vacuum I had reduced the richness of the idle mixture slightly, and closed the rear butterfly a smidgen.

I hope to get an O2 sensor on it this weekend and get some other info, but I am confused about the exhaust temperatures and the fact that the timing seems to be shifting. It has a new balancer and I doubt it is moving, but I may have to check it. The bolt was tightened enough that I couldn't move the distributor without backing it off. I also note that this is not the first time I've been surprised that the timing didn't seem to be where I left it.

[mike7570]

sure the guys at the exhaust shop didn't fool with it and take it out for a spin, they had it for a week?
It was at 28* initial without the vacuum advance hooked up, nobody touched it?
I would re-check TDC, reset valves and timing, change the plugs and maybe even the plug wires and also check for vacuum leaks.
If everything checks out good then I would get into adjusting the carb.

[Yellow Truck]

Mike - thanks for your thoughts. I did a vacuum test, it has no leaks. I've known the guys at the shop for 10 years, they are too busy to joy ride, besides they have cooler rides around than mine! They did keep it for a week but I told him I wasn't in a hurry, and then our first bunch of winter storms blew through and I didn't want it back.

I am curious about the timing moving around - I was sure it happened before but doubted myself. This time I'm positive. I'm going to check TDC and the valve lifter pre-load before I mess with the carb, but I'd like to have the O2 sensors in when I start it next.

[68fecyclone]

just a thought here, I don't know what distributor your using, but maybe the advance weights are sticking causing you to see different numbers each time you check the timing, or the point plate is loose and moving around.  Rob L

[Yellow Truck]

just a thought here, I don't know what distributor your using, but maybe the advance weights are sticking causing you to see different numbers each time you check the timing, or the point plate is loose and moving around.  Rob L

Since I just had it re-curved I hadn't thought of it, but it is a good idea. The plate is simple enough to check.

[blykins]

The difference in the preload amount is this:  most engines have stud mounted rocker arms, with the polylock/lock mounted on the trunnion of the rocker arm.  On an FE, the adjuster is hanging off the rear of the rocker arm, in direct line with the pushrod.   Due to geometry differences there, a half turn of the adjuster on an FE will not get you the same amount of preload as it would on a SBF, SBC, etc. 

As for the other stuff, sounds like your truck had been tampered with. 

[Yellow Truck]

Brent, I was thinking something similar, the rocker ratio on an FE is different. What I noticed was, when I was doing the one full turn after making contact with the pushrod, the valves were moving. That was on a cold engine.

I also don't understand the temperature readings. I think I'll try a different meter.

[blykins]

Well, it's not because the FE rocker arm ratio is 1.76 vs. another ratio, it's because of where the adjuster is on the rocker arm....

If you're doing one full turn and the valves are opening, then either the lifter has been pumped up with no preload and it will take a little bit to bleed the oil out, or you've measured pushrod length incorrectly.

[Yellow Truck]

I've been wondering about the pushrod length. We measured with a measuring rod, following the instructions from T&D - I soaked the lifters in oil, and put them in the engine, rotated it to the base circle for each valve on 4 cylinders (we didn't do all bolted down the rocker assembly, and turned the adjuster down one full turn, and threaded the pushrod out until it made good contact, removed it and measured it.

On the original set up we turned the adjuster down until it made contact with the pushrod (about one full turn), then two more turns. I don't recall us noticing the rocker or valve moving.

What I found when I re-did the preload was that the adjuster made contact with the pushrod at about 1/4 turn of the adjuster, and beyond that it was moving the rocker and valve. I followed Barry's instructions I did the adjustment on a cold engine - one full turn after contact with the pushrod, and didn't take any measurements to see if the lifter bled out and let the valve return to closed.

The T&D instructions are imperfect at best:
“Seat the bottom of the adjuster screw up against the recess in the rocker arm and turn the adjuster screw clockwise one full turn down. This is the initial adjuster position. Adjust the pushrod length tool to the proper length, remove from the engine, and measure its overall length.

The rocker arm should not be operated with the adjuster screw more than one turn up or down, from the initial adjuster position. Doing so can cut off the flow of oil to the rocker arm.”

But as I interpret them so long as the adjustment is between fully backed out and two turns down, it should oil correctly - the "initial adjuster position" is one turn down, and it should not be operated more than one turn up or down.

[blykins]

You need to back the adjuster all the way out, screw it in one full turn. 

Put the lifter on the base circle of the camshaft, EVO, etc. 

Screw your adjustable pushrod out until it hits both the lifter cup and the rocker arm cup.  Add .060" for preload.   If you have the intake off the engine, you can take a lifter with no oil in it, push the plunger down and stick a .050-.060" paper clip between the circlip and the shoulder of the plunger.   Then you just run your adjustable pushrod between the rocker arm cup and the lifter cup. 

I wouldn't advise soaking hydraulic lifters in oil before installation.  It's not a cardinal sin, but it can make things a little difficult when measuring and on startup, because it will hold the valves open until the lifters bleed oil out (which may take a bit).  I always coat the outsides with oil and just drop them in.

[Yellow Truck]

Well, I had some time to work on it over the past week, and because I've seen some strange changes in the initial timing, I started by pulling the distributor. The gear is in place (can see through the roll pin), the gear is not worn, the weights are moving nicely, and the top plate is free to move under vacuum advance. While I was putting it back in I noticed a small pool of oil on the intake, and there were some cracks in the ignition to coil wire. Thought the oil was a valve cover leak, but it seemed odd. Took the coil off (and fixed the cracked wire) and found the coil was the source of the oil. Put on a new coil and put in some new plugs (it is very sensitive to fouled plugs), and today I got it lit. I had noticed that I had an extra helper:


With some assistance from a friend I got it started and got the timing set in around 14 degrees and it ran quite nicely - settled down to an acceptable idle. Ran it up to 3,500 RPM to check total timing. Then we noticed I had had a LOT of help from one of my little neighbours:

With the exhaust clear, we took it out for a quick run and it ran like a scalded cat - as well as it had before it suddenly started running like crap. So far so good. When we got it back we noticed it was now ticking, a little stethoscope work and we determined it was the driver side valve train so we pulled the cover and found some of the pushrods a little loose. Did a crude quick adjustment and started it - the tick was gone so we confirmed the cause but now one of the valves seems to be hanging (low vacuum, cool exhaust on one side, running rough) so I'll re-do the pre-load on that side tomorrow.

One interesting thing, the timing has had a tendency to move around. I had my buddy bring over his timing light so we could compare - I wanted to eliminate a possible bad light. They showed the same, 13 degrees initial advance, vacuum took it up to 21, and at 3,500 rpm it was showing about 42.

Next, we tapped on the vacuum canister while it was idling and with each tap the timing dropped, eventually dropping from 14 to about 3 degrees. Not sure what to make of that, but the shaft seemed to line up poorly with the pin on the top plate, so we made a few adjustments to get it to fit better. Made up my own little vacuum tester and here is what we saw in the distributor when we put some vacuum on the canister:
 https://youtu.be/eMpCn7vjWac

Right now it is running well enough that I'm not concerned about the actual build. I'll get the pre-load right and put it away until spring because winter is near. In the spring I may just put a new MSD distributor on it since it is kind of silly to spend that much on the engine and still run a 45 year old ignition. I'll also put an O2 sensor and computer into it.

[Yellow Truck]

Adjusted the pre-load and ran it this afternoon. Nice dat to work on it - sunny, still, and mid sixties. After the adjustment it ran beautifully. Still need to break it in and get the carb and timing optimized but that will have to wait till spring.

Thanks to everyone on this site and to Barry R for your help. Your expertise is invaluable in keeping the FE alive.