Butters - Jeff's 81 Scrambler Build Thread

[hefavitzen]

Do you guys trim the gasket so that it fits the port perfectly? These hang over the edge just a little on the center divider. I was thinking about trimming it down a little to fit though I am a little nervous about screwing it up. ha

 

[mysunnshine]

I trim gaskets to fit but that's just how I am........ I use a sanding drum.

 

[jammer1]

I agree, there is a LOT of room on the outside of each port.

Here is a screenshot of a Fel-Pro 1255. As you can see, the ports are canted just like the heads ports are. This looks like a much better fit, though it is a composite gasket. Summit has good ratings for it.

As you can see, the old gaskets were truly a rectangle instead of somewhat canted like the actual head ports.
View attachment 109107View attachment 109106
So, I was looking through the documentation of the build on my engine. My intake is an Edelbrock Performer for Vortec, PN 21163 and in the instructions I see it calls for a specific gasket - Edelbrock #7235 Port: 1.08” x 2.11”, .120” Thickness. The Fel-Pro 1255 also has those same specs, 2.110 in. x 1.08 in. Port, .120 in. Thick. Both of these gaskets look identical and have the "canted" ports, or ports that are not straight up and down.

But, that is not what I found on my engine when I pulled the gasket. I found instead is what appears to be a Mahle MS16167 gasket which is hard plastic and has large rectangular ports that are straight up and down, which are MUCH larger than the ports on my heads.

I am hoping he had a good reason at the time for the swap, but heck if I know. I'll post and update when I pick up the Fel-Pro 1255 gaskets today.

The edelbrock ones the mechanic tried were composite and the same openings like this one. You saw the results in a little over 300 miles, 6 mths. I worry about the lack of bolts in the center of the intake. Oem reinforced this section in a rigid for a reason. From what I read the plastic breaks down/drys out. Didn't like the way my gaskets looked. If you use the ms 98000 make sure you stick to their specs for tightening. Me I don't worry about a perfect match. Mines a Jeep that doesn't see over 3,200 rpm, not ment to be a race engine.

 

[hefavitzen]

Hey Guys, so here is the latest issue I am facing: My distributor, at TDC, is pointing at #2 instead of #1.

I verified that I am at TDC by checking that both valves are closed and the piston is at the top of the cylinder with a borescope. I could visually see that it is at the top of the stroke.

But, as you can see, the distributor is pointed at #2 instead of #1. Any ideas what is up?

 

[hefavitzen]

Hey Guys, so here is the latest issue I am facing: My distributor, at TDC, is pointing at #2 instead of #1.

I verified that I am at TDC by checking that both valves are closed and the piston is at the top of the cylinder with a borescope. I could visually see that it is at the top of the stroke.

But, as you can see, the distributor is pointed at #2 instead of #1. Any ideas what is up?

I figured it out. I put a big screw driver down the distributor hole, lined the oil pump slot up with the #5 cylinder and the distributor dropped right in pointed directly at cylinder #1.

Cool!

 

[mysunnshine]

Have you recurved that distributor or are you still running the two large silver springs that came in it?

 

[hefavitzen]

I did recurve it with a blue spring and a lighter silver spring. I think it should fully advance by 3200 rpm. I need to get a coil wire, a new bit for my rivet nut driver that I broke, and wire power to the new distro.

Then I'll set timing and hope it holds the gasket for a good long time.

 

[hefavitzen]

Well, I got it back together and have struggled with getting the timing dialed in.

The distance I can turn the distributor and have it run "ok" is tiny.
Even timed at 32 to 34 degrees advanced it still wants to spit and pop a bit.
I did not get to drive it as I need to reseal the water neck and ran out of daylight.

I did a voltage check and the switched power to the distributor was between 10.5 and 11.9 volts tops, so I am going to put a relay in line to give it a full 12 volts all the time.

Once I get the water neck resealed and the relay in place I'll revalidate that I am at TDC on the Compression stroke and then time it again and see where I am.

 

[mysunnshine]

Does it spit and pop out the intake?

 

[hefavitzen]

Does it spit and pop out the intake?

It did at first, then I turned the distro counter clockwise (from left to right) a bit and it stopped doing it so badly. It just isn't smooth. Even my wife, who couldn't give a flying rat about cars in general, thought it sounded not as well as she expected it to.

I have the water neck off at the moment due to the leak, but as soon as I have it resealed I'll restart it and see what is what. I slept on it and now I am not 100% on the sound. It was a long long long few days of wrenching, looking things up, learning some things, wrenching some more, looking things up, learning more new things, wrenching some more. Whew! I have always enjoyed working on cars, but I do have even more respect for people who do this for a living.

 

[trust]

Yes, I was recently humbled by a shop of true professionals, totally put me in my place as it were... good thing they loved the scrambler enough to overlook or at least ot pou t and laugh at my feeble attempts

 

[trust]

At least not point and laugh

 

[hefavitzen]

At least not point and laugh

Andy Zuber, a friend who has helped me a lot with advise over the years and has done some excellent work on my Scrambler, correcting things I screwed up such as putting in a new wiring harness correctly. He has worked on 4x4's and Jeeps for many years and a few years ago he had begun working for Retro Designs. We were talking last year about axles (he was helping me correct a mistake I had made after not taking his advice in the first place...he's been very patient) and he'd been at Retro Designs for about 4 or 5 months. He said he's learned so much from the guys there, such as he would have rewired it differently. There is just no end to the learning.

 

[hefavitzen]

Update as of 5/22/2023

1) I got it all buttoned up but DID NOT check the oil / oil level
2) I set the timing and find that with the new distributor, it is VERY precise, meaning that a tiny turn makes a big difference. I set timing for 32 degrees, with a blue and silver spring (but not the heavy springs the distro came with).
3) I took it on a 1.5 mile drive and it was fantastic...but I noticed that the oil pressure gauge was pegged at max. It's a Speedhut gauge that reads 0-100psi.
4) I checked the oil when I got home and found that the oil was WAY up the dipstick and that the way the oil separated along the dipstick that it probably was not all oil. I am hoping that coolant leaked into the crank case during the intake gasket swap and is not currently leaking into the crank case.
5) I changed the oil and didn't find it overly noxious with coolant, so refilled and changed the filter.
6) I checked the radiator and found the coolant there looking like coolant with no rainbows present.
7) I checked the oil pressure switch to ensure it was plugged in correctly and found that it was. I unscrewed it from the back of the block and inspected it and it looks ok, but I can't see the diaphragm inside so what do I know.
8) I did try to test it with a multi-meter but my meter-skills are pretty lousy so I never got more than a zero conduction reading. I am not sure if I tested it correctly or not, though I did look up methods to do this on the YouTubes.
9) I went in search of a new sensor at O'Reillys and Advanced Auto and we could never find the correct switch in their DB. All the switches they had in stock had a 1/4 npt fitting instead of the 1/8 npt fitting that I have.
10) I did find the part on Summit (SEN-03-8) which is a Dakota Digital switch. It is identical in every way to the switch I have and is probably what Speedhut was using at the time I bought my kit. Today they have their own set of switches with a 1/8 npt thread, but I decided to replace with what I already have.

My new switch will be here Tuesday or Wednesday so I'll install it and let you guys know how it goes! Ugh...two steps forward...

 

[hefavitzen]

Here is how to determine if your Dakota Digital or likely any 100psi 3-prong oil pressure sensor is bad.

I contacted Dakota Digital tech support and here is what they said:

It is a 5 volt sensor between the red and black wire, the white wire is the voltage return. 0 psi it should return about an half a volt on the white wire and 4.5 volts at 100 psi. If the ground is missing it will read about 3.5-3.8 volts just with key on engine not running.

Sam Hoffart, Technical Support, Dakota Digital, Inc, Email: SamH@dakotadigital.com, www.dakotadigital.com

I was nervous about testing the sensor under power because this meant I would have to at least poke a multi-meter lead into the wire casing. I said as much to Sam and he said, "That is exactly what you'll have to do.", so I did. (Sam was very helpful, actually answering 4 or 5 emails from me throughout the day.)

Here is the old sensor and it's reading with the multi-meter. I am touching the white wire with one lead and the other grounded on the block.
It reads 4.95 - or with the key on and the sensor out of the engine it is reading 100psi. Not Good.

So, here is the new sensor attached to the wiring. It reads .531 or 0psi -
This is Good!


Now with the engine running it reads 40psi. Much better.

Also, Sam was interested in hearing more about Speedhut using a Dakota Digital sensor in their kit. I explained I was probably customer #1 or #2 for this kit and today they apparently sell their own sensor because this specific sensor isn't available on their site (had to hit up Summit).

 

[hefavitzen]

So, after taking it out for a few drives and seeing how it feels hot and cold, going easy and scooting down the road I still feel it is missing. Not all the time, but a lot of the time, especially after driving a bit, stopping and idling, and then getting underway again (like driving to my son's school, waiting in line, taking off again).

So I used an endoscope of better quality today and even took some pictures that I'll post in a bit.
What I see is that in the #8 cylinder there is fuel/oil pooling in the cylinder and what appears to be a wet seam between the head and block.

I checked the other cylinders and did not see this elsewhere.

 

[hefavitzen]

So I've pulled the head off and am looking at the valves and going to replace the valve seals and keepers along with cleaning up the valve seats. Upon inspection of the #8 valve I noticed that it is very pitted on the sealing surface. I am cleaning it up, but it looks like I may need to replace this one.

This photo is after using scotch bright on it to clean the carbon off.

 

[Chamba]

We're you getting any pinging? Looks a bit like the timing was too far advanced giving you pre-detonation.

 

[hefavitzen]

We're you getting any pinging? Looks a bit like the timing was too far advanced giving you pre-detonation.

I was getting pinging. To be honest, I've only recently learned how to correctly set timing and that coupled with a distributor that was against the firewall with the engine off and likely really being pressed on when the engine is under load, my timing in the past was probably terrible.

So, I've replaced the distributor and am replacing this valve and checking the others. At least the head doesn't have pitting where the valve will seal. I was pretty relieved to see it was clean and smooth.

 

[hefavitzen]

OK, as I was rebuilding the heads I put my old spark plugs in to keep the threads clean while I repainted and I realized that my plugs weren't anywhere near the top of the head, like, they are buried in the threaded spark plug hole. I did some searching on Summit looking at the specs for the heads I had bought in 2015 and found someone else who asked what spark plugs were supposed to be used. I'm pretty sure I've never used the correct plugs...daggumit.

See for yourself. Proper Spark Plug Reach for the Win!!!