I can't drive 55

[zerotreedelta]

I'm definitely puzzled.
* Gearing seems correct (2100 @ 45 mph)
* Plugs don't look too bad, so AFR doesn't seem all that far out of whack and seems like running on all 6
* Doing a WOT throttle pull would minimize most vacuum related issues (vacuum advance, etc).

The two HouseMD differential diagnostics I'm curious to see are if the mechanical advance is working (or if it's all-in at idle due to weak springs) and the compression results. Carb swap will also be intriguing...

 

[pb4ugo]

I think carb and fuel delivery issues are 1 in the same. Along with vacuum.

 

[pb4ugo]

If it was fuel pump or float issue, I think it would be surging at wide open throttle.

 

[MatthewMcD]

I'm definitely puzzled.
* Gearing seems correct (2100 @ 45 mph)
* Plugs don't look too bad, so AFR doesn't seem all that far out of whack and seems like running on all 6
* Doing a WOT throttle pull would minimize most vacuum related issues (vacuum advance, etc).

The two HouseMD differential diagnostics I'm curious to see are if the mechanical advance is working (or if it's all-in at idle due to weak springs) and the compression results. Carb swap will also be intriguing...

The compression numbers are in that same previous post.

 

[MatthewMcD]

I think carb and fuel delivery issues are 1 in the same. Along with vacuum.

I separated them as there is an un-rebuilt fuel pump and 2 fuel filters that I just replaced.

 

[zerotreedelta]

I tried to reread everything, missed the compression when I got distracted by the plugs.

Needed to run an errand, so I did my own little "self-inflicted infection" test. You can set the Hyperspark to override with static timing, so I pegged it at 12*. It'll row through 1-3 and into 4 pretty well, but you can tell it starts to lay over around 45-50 due to not enough advance for the RPM and therefore not getting the power out of the piston stroke. I could pull 60, but it wasn't snappy getting there.

Might not be it, but it was an interesting test nonetheless.

 

[charliemeyer007]

What - no all of the above?; loose nut behind the wheel and widget arm on the maniform

 

[zerotreedelta]

"Parasitic drag" could be actually an extra option.

I'm waiting for a video like this after all the tuning (courtesy of Australia)...wonder how a 2F would like a blower up top.

 

[Grayscale]

To me, they look good. But you tell me what you think: I can't drive 55 - https://forum.ih8mud.com/threads/i-cant-drive-55.1347969/post-15666353

I think that number one is looking a bit lean, maybe number 5 as well - it is hard to say from the photo and the light. I'd try to clean #3 by swapping it with the plug in cylinder #1, if the insulator goes white, you might consider something at the manifold gasket. On the three heads that I've tinkered with, they all had globs of caked-on polymerized oil, on the intake valves. If the valve stems seals are leaking, which they were to some extent in all three of mine, then it could be that your vacuum is fine at idle, yet diminished at higher rpm?

I'd assume that the PO was honest about getting it to speed. You reported that the, "the truck sat for a LONG time," so a bit of fuel-varnish or even corrosion in the carb might be a fuel restriction?

I think you are on the right track, with a solid game-plan, it might be a while.

That carburetor looks dirty; it probably needs a carb-dip and rebuild kit. My truck ran really bad with the Weber 32/36, it didn't like heavy throttle, but, it was a junk-yard engine that I knew had clogged valves, and was getting cleaned out just with running fresh gasoline. The Weber might be just fine getting you up to speed, at your altitude, maybe even using it as a 'runner' as you sort things out. Does the air cleaner assembly that you have appear to be for a '68-ish one-barrel carb, or a later two-barrel F, based on the diameter of hole where it meets the carb?

 

[knuckle47]

Well … we installed the French doors in the new room, removed the old 3’ header and added a 7’ one, cut the hole in the wall and made new jack studs…I am freakin’ wasted. As I sat down to shake the sawdust from my eyelashes, I remembered the saga of the 45 mph FJ40 and just tuned in and read two more full pages of post and hoping to read an answer soon…good luck!

 

[45Dougal]

Fwiw I'm running with fuel delivery; water in the filter, blocked vent, rusty crap blocking it up, perished hoses, too many filters for the pump etc
Can you blow the fuel line back?

 

[MatthewMcD]

I think that number one is looking a bit lean, maybe number 5 as well - it is hard to say from the photo and the light. I'd try to clean #3 by swapping it with the plug in cylinder #1, if the insulator goes white, you might consider something at the manifold gasket. On the three heads that I've tinkered with, they all had globs of caked-on polymerized oil, on the intake valves. If the valve stems seals are leaking, which they were to some extent in all three of mine, then it could be that your vacuum is fine at idle, yet diminished at higher rpm?

I'd assume that the PO was honest about getting it to speed. You reported that the, "the truck sat for a LONG time," so a bit of fuel-varnish or even corrosion in the carb might be a fuel restriction?

I think you are on the right track, with a solid game-plan, it might be a while.

That carburetor looks dirty; it probably needs a carb-dip and rebuild kit. My truck ran really bad with the Weber 32/36, it didn't like heavy throttle, but, it was a junk-yard engine that I knew had clogged valves, and was getting cleaned out just with running fresh gasoline. The Weber might be just fine getting you up to speed, at your altitude, maybe even using it as a 'runner' as you sort things out. Does the air cleaner assembly that you have appear to be for a '68-ish one-barrel carb, or a later two-barrel F, based on the diameter of hole where it meets the carb?

I totally rebuilt the carb back in January and made sure every circuit was clear. I did not spend time on the exterior because I knew, eventually, I was going to ditch it.

You can see the air cleaner in this post. I can't drive 55 - https://forum.ih8mud.com/threads/i-cant-drive-55.1347969/post-15670372 the janky connection is not great, but it does fit this carb.

 

[MatthewMcD]

Fwiw I'm running with fuel delivery; water in the filter, blocked vent, rusty crap blocking it up, perished hoses, too many filters for the pump etc
Can you blow the fuel line back?

Not sure what you mean. I replaced the fuel filters and the fuel is definitely flowing. I bought a tee so I can get a fuel pressure reading.

 

[MatthewMcD]

Long damn day! Lots of diagnostics and began the carb swap by removing the old carb. BTW, I LOVE this timing light. Thanks for the recommendation @knuckle47 and @RevISK so much easier than juggling 3 different devices.

• Distributor Advance - I measured 22* at 1000 rpm. It appears to be working. Now I need to know what the progression should be through the RPM range, the FSM is confusing.
• Dwell - 40*
• Vacuum at ~750 RPM - 19"Hg

I recorded a video of 1-4 but managed to misplace the memory card from my GoPro. When I find it, I'll post it.

 

[MatthewMcD]

Clutch inspection has been on my list for a year. It feels very solid but I need to see it. I opened the inspection cover for the first time and was shocked that there were no wasps or remnants of ratatouille. The interior of the bell housing is dry, the pan has some oil and I found this clip laying in the gunk.

Pressing the clutch pedal exposed a hairline separation in the friction material.

Is this a Napa item? Looks like I'll be dropping the tranny after I get the new carb installed.

 

[zerotreedelta]

As far as timing goes, was that mechanical only (no vacuum advance)? This was my timing map that was intended to replicate factory, albeit for the 2F vs older F...I don't have that FSM.

Looks like I ramped from 9-10 base (slightly more than factory) up to 22-23 by 3200RPM at WOT (basically the top row) to account for the mechanical advance, and then you can see how it brings what would be vacuum advance as you go down the rows to the lower MAP readings.

At least for the 2F, advance starts around 1000RPM flywheel (500RPM camshaft), but only getting to around 8-10 mech' advance by 1800 RPM.

Original post re: timing:

FiTech/Sniper Distributor ???

Bumping an old thread. I was looking online and saw Holley now makes distributors for a Chevy straight 6. Does anyone know if this is one of the applications you can swap a Toyota gear onto and run in our trucks? I dont know enough about the GM inline engines. It looks like it is set up to...

forum.ih8mud.com

 

[zerotreedelta]

Oh, and clip is likely from the throwout bearing arm...you might want that back in there.

 

[MatthewMcD]

As far as timing goes, was that mechanical only (no vacuum advance)? This was my timing map that was intended to replicate factory, albeit for the 2F vs older F...I don't have that FSM.

Looks like I ramped from 9-10 base (slightly more than factory) up to 22-23 by 3200RPM at WOT (basically the top row) to account for the mechanical advance, and then you can see how it brings what would be vacuum advance as you go down the rows to the lower MAP readings.

At least for the 2F, advance starts around 1000RPM flywheel (500RPM camshaft), but only getting to around 8-10 mech' advance by 1800 RPM.

View attachment 3748398View attachment 3748399

Original post re: timing:

FiTech/Sniper Distributor ???

Bumping an old thread. I was looking online and saw Holley now makes distributors for a Chevy straight 6. Does anyone know if this is one of the applications you can swap a Toyota gear onto and run in our trucks? I dont know enough about the GM inline engines. It looks like it is set up to...

forum.ih8mud.com

Good point, I did not disconnect the vacuum advance, so this is a "combined" number. I need to do more testing once I get the engine running again with the Weber.

 

[MatthewMcD]

Oh, and clip is likely from the throwout bearing arm...you might want that back in there.

View attachment 3748403

Added to the list for tomorrow. Thanks!

What should it look like normally, hard to tell from your photo?

 

[zerotreedelta]

Been a bit (time flies, I got a "remember this day 3 years ago" of final assembly today!)...but I recall that small tab/bend going into a longitudinal hole here, basically to retain it. (I want to say there's one on each side, too?)