Out with the old...





More or less on pace to have the new engine installed next weekend. Discovered a cracked ear on the old Offenhauser intake so I'm dropping it off with a welder on Monday.

 

How's it coming?

 

Oy, I had the engine lined up with the tranny and was trying to get the clutch lined up with the input shaft when I noticed the new block plate was wrong. So had to abort until I could get the old block plate off and installed on the new engine. That was three weeks ago - had a couple of events the past two weekends and didn't have a chance to fool with it. Going to take another crack at it on Monday.

I had to get a welder to shore up one of the mounting ears on the Offenhauser intake as well and was able to pick it up this week. So with luck I'll be breaking in the new engine Tuesday or Wednesday.

 

How goes the progress on this?

 

I got the new engine in the previous weekend, but it was on the engine perches and the transmission was still ~1" from being mated to the block. So I went underneath the truck this past weekend and removed the transfer case and crossmember so I could more easily slide around the transmission. Finally got the transmission mated up to the block yesterday.

I don't know if the old engine mounts were just really shot or what, but the transmission is about an inch farther forward now. I relocated the crossmember when I swapped in a ZF, now with a little modification I'll be able to move it back to the original spot. I hope. If not I'm going to have to modify some more so it will fit back in the new mounting spot.

So there's modifying the crossmember and remounting the transfer case, then just need to install the intake/exhaust, starter, fuel pump, radiator, belt and hoses, spark plugs. Bleed the new clutch slave. Should have it driving by Sunday.

 

Finally started the new engine on Saturday and ran it for 20 minutes or so at the recommended 2,000-2,500 rpm. It fired right up on the first crank, no worries, but once I let my foot off the gas it died. Changed the oil today and started it up again - it will not idle. Seems like a bad vacuum leak. The intake/exhaust manifolds are dick tight, torqued in sequence to spec per the manual and rechecked today. Everything else on the intake and carb looks fine, double checked the carb nuts were tight, all vacuum lines and can't find any obvious leaks.

Tomorrow evening I'm going to check all the spark plugs, wires, cap, rotor, etc. to confirm no issues there.

Also got no reading on the temperature gauge throughout the break-in so I need to check that out.

 

Glad you got it all fired up! Fortunately, no idle is generally an external thing, like carb or vacuum.
Hopefully you can track down what the issue is and get it out on the open road.

 

As I suspected it's a vacuum leak. I blew cigar smoke through a hose attached to the vacuum tree and it came billowing out around the #1 & 2 intake runners right at the gasket face. Double checked the torque on all the retaining nuts and it's still leaking. I won't have a chance to remove it until the weekend. It's a Mr Gasket 260 so I'm a little perturbed. I reckon I'll check to see if there's anything physically damaged/wrong with the intake, and if not, put a bead of sealer around all the runners and reinstall.

 

When was the last time you checked your manifolds for flatness?
I had that issue and had a tab that was ever so slightly curled inward. I had it welded for strength and then machined flat again.

 

Can't say for sure the last time I really checked the intake, but I can say for sure when the next time will be. I thought about having the machine shop sand it flush but decided not to, also considered getting a Remflex gasket but didn't since I had the Mr Gasket sitting around.

So I'll remove, inspect, and apply some high temp RTV around all the intake and exhaust flanges.

 

I have had good success with mating surfaces sanded as you described.

 

Sometime back, did you mention having success with soaking the gasket in water before installation?

 

yes, that makes it less prone to damage on installation.

 

Well this is rather embarrassing. Took advantage of our first bit of fall weather here in north Texas and pulled the intake this afternoon. I obviously didn't even look at the gasket face before installing it. There were pieces of the old gasket stuck on all the intake runners. Geez, what a maroon.

 

Just be glad you didn't bust it! I've done that before (so don't feel too bad), but when I did, it snapped the ear right off. My intake has a nice weld line as a scar from it.