Rough idle, compression test... head gasket at 3 and 4? (1 Viewer)

MoaByte

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Don't adjust carb until valves and timing are good. A stethoscope can tell you a lot. This is the fun part.
 

MoaByte

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I admire that that the emissions didn't scare you into handing it off. This is a cool thread.
 

DFXR

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Thanks all. The thing about the emissions stuff - after 10 years it is less scary than it is aggravating. Getting all of it off and then on again (especially the EGR) bookends any engine/manifold project with time and headache. Looking at a desmogged or older 2F just makes me wistful. Sh*t like this could almost be fun. But then you find yourself wrestling with the EGR "won't flex" hose and thinking about selling the thing as soon as you're done.

I have timed with my vac gauge before, and it's fun in an old hot rod way, kinda like pouring water into your carb (google that), but I get better results with my really basic timing light. I usually time it, then hook up the vac gauge and set the idle to best reading on that. That's the plan at least!

I'll keep you all posted.

Thanks again to @lcolon for his great head removal thread-
 

MoaByte

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Thanks all. The thing about the emissions stuff - after 10 years it is less scary than it is aggravating. Getting all of it off and then on again (especially the EGR) bookends any engine/manifold project with time and headache. Looking at a desmogged or older 2F just makes me wistful. Sh*t like this could almost be fun. But then you find yourself wrestling with the EGR "won't flex" hose and thinking about selling the thing as soon as you're done.

I have timed with my vac gauge before, and it's fun in an old hot rod way, kinda like pouring water into your carb (google that), but I get better results with my really basic timing light. I usually time it, then hook up the vac gauge and set the idle to best reading on that. That's the plan at least!

I'll keep you all posted.

Thanks again to @lcolon for his great head removal thread-
You are golden. Slightly better than chrome and way better than chrome painted with plasti-dip. Lol
 

DFXR

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You are golden. Slightly better than chrome and way better than chrome painted with plasti-dip. Lol
Checked the valve lash and yeah, most were a little tight, not crazy tight, but maybe just an ass hair past dead on... Opened up all intakes a tiny bit, all exhausts a little more.

Idle has now smoothed out at 750, and that’s without any carb adjustment. Valves nice and loud. Took it for a longer drive, including a nearby “test hill,” and the warm vacuum reading was a steady 19.

I may advance the timing from 7* to 9* for a little more pep but mostly I just need to drive it.
 

MoaByte

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Checked the valve lash and yeah, most were a little tight, not crazy tight, but maybe just an ass hair past dead on... Opened up all intakes a tiny bit, all exhausts a little more.

Idle has now smoothed out at 750, and that’s without any carb adjustment. Valves nice and loud. Took it for a longer drive, including a nearby “test hill,” and the warm vacuum reading was a steady 19.

I may advance the timing from 7* to 9* for a little more pep but mostly I just need to drive it.
Did you adjust them with the engine running? 😆. I tried that.. checked them with engine running but adjusted them with ignition off.
 

DFXR

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Did you adjust them with the engine running? 😆. I tried that.. checked them with engine running but adjusted them with ignition off.

Yeah man, I hold the flathead in my teeth, next to my unfiltered Pall Mall. The smoke keeps my mind off the pain!

I do them cold, because I work slow, and I also wantted to check the torque on all the head bolts before doing the valves.
 

Zjohnsonua

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Somewhere there's a kid that needs to read this thread to realize that this is what old cars are all about. No computers, scan tools, etc... just ol' reliable diagnoses, repairs, and recommissioning. I'm getting ready to yank both of my 2Fs, but I'll admit that threads like this one at least give me pause before I do it.

Happy wheeling. :cool: :beer:
 

MoaByte

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Yeah man, I hold the flathead in my teeth, next to my unfiltered Pall Mall. The smoke keeps my mind off the pain!

I do them cold, because I work slow, and I also wantted to check the torque on all the head bolts before doing the valves.
Then adjust your timing by setting a cold glass of whiskey on the air cleaner. Lock it in when the waves are smoothest😉👍
 

DFXR

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Then adjust your timing by setting a cold glass of whiskey on the air cleaner. Lock it in when the waves are smoothest😉👍
Update here. Got about 100 miles on the new head, no big long “crucible” to truly test it but all is still well. Running at normal temps according to the little digital temp gauge I installed when I put it all back together.

What I’ve done this week:

Switched back to stock Denso plugs from NGK BPR4ES
Advanced timing from 7 to 9 degrees
Re-torqued head bolts ( a couple moved a hair)
Re-torqued rocker bolts
Checked valves after all that
19.5hg and steady

There is a little exhaust leak somewhere. I am pretending not to hear it.

AND... I bypassed my rear heater a while ago, so before I put the head back on I put in the slick little Toyota SS “joint” to replace the stock heater cactus thing. Turns out that if you still have your air rail in place, the new joint puts the heater hose really close to it. I know the air rail doesn’t get nearly as hot as the manifold but it was still making me think about it, so I switched back to the cactus (with a pipe plug in the side port). That puts the hose back up where it belongs.

Maybe these before and after pics will help explain:

5C4F4A57-DA22-42FF-B132-70D303994C45.jpeg

3317CBA1-D652-49C4-A8B2-919CB39BC9AD.jpeg

D7DA32DD-14DD-44D4-9272-9D0450A2D5B7.jpeg
 

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