Rebuilt engine, now to make it run...

Well! I rebuilt my L134 this past winter and finally have it and the rest of the chassis done and assembled.

Last night I tried to get it to run, (no luck) and I wanted to share my experiences and see if anyone has any ideas to get this running.

The motor started out as a stock/never bored, but previously rebuilt L134 (1947 CJ-2a). It ran well, had good power (had it up to 59mph once) and had about 90-100psi on all 4 cylinders. I only tore it down because it leaked like a sieve.

After getting it torn down and hot tanked and inspected, I decided to go for a full rebuild since a number of things were a bit marginal. I had the following done:

Block bored to .040
Block decked (milled) down .020"
Valve seats done and hardened inserts installed in the exhaust side.
New valves, guides, adjusters, springs and lifters
Clifford reground my camshaft
Head milled about .020" or so (which happened to be a GPW head)
New pistons/rings

(Note: During assembly I noticed that the pistons came up even with the deck of the block, maybe a couple thousandths of an inch above the deck. I placed the head on there, no gasket, no bolts and turned the crankshaft over, in any case the pistons did not protrude enough to lift the head off of the block. I believe my piston to head clearance is roughly equal to my head gasket thickness, no more. I tried my best to "CC" out my combustion chambers and estimate the compression ratio to be about 7:1).

Rods checked/inspected and okay
crank inspected and polished
new bearings throughout (I checked the fit with plastigage and they were in spec, ~.002-.003" clearance I believe).
new mallory oil pump
welded timing gear squirter closed and redrilled to later model spec of .040" (stock for my year was .070")
New timing gears
New head and manifold studs. All studs that went into the water jacket got a coat of a high temp thread sealant.


So now it's back together and it won't run. Here's what I can tell you.

I left the carb alone, it has not been touched since removal last october.
I left the distributor alone, it has not been touched since removal.

When the head was off I set up the oil pump at TDC/#1 compression stroke and made a mark across the front pulley and timing cover. (I know about the markings on the flywheel, but haven't used them for reference yet). Later with the head on, I installed the distributor body 180 out from how I originally found it, simply because that seemed like an arbitrary thing and I just did it the way the manual showed it (the coil wire screw faces down towards the ground). With the rotor on at TDC, it points generally downward. I set the distributor so that the rotor points exactly at my #1 wire.

I installed the wires counter-clockwise, 1-3-4-2 as labeled on the head. I assume this is the right order, right?

I primed my fuel system with a vacuum pump. I can see fuel in my clear fuel filter housing.

I primed the engine oil by some creative line routing to the oil filter can. I pulled the filter out, filled the can full of oil and applied 25psi air to the top fitting. I re-routed the bottom fitting on the can to the oil main.... I saw ~20psi oil pressure on my engine oil pressure gauge and pumped ~1 quart of oil through the system this way. (and about 1 qt all over the garage as well..... R)

With the ignition hooked up (I ran a wire from the battery to the ballast resistor to my original coil and hooked the other lead to the distributor), I cranked the motor over. After a 1/2 dozen cranks it fired very briefly. Then nothing. I kept cranking it finally got another "vroom, pahhh" (back through the carb). And that was it.

I had about 40psi oil pressure during cranking (btw, 6volt starter, 12 volt battery, it cranks fairly well )

More cranking = nothing.

I yanked the #3 plug, laid it against my ground strap and cranked. I saw a blue spark. I have no idea what a good or bad spark looks like. My friend had a spark tester device that you thread one end in/out on to adjust the gap. Where he normally has it set is about 1/4" gap (which seems HUGE to me!) and on that, or even at .10" there was nothing. This tester went all the way out to almost 1" gap (if you wanted to adjust it that far). I've never seen a tester like this before and don't know what to expect. 1/4" gap just seems enormous to me though.

I hooked a compression tester to the #3 cylinder and saw 90psi. A little low, but the rings aren't broken in yet.. so...?

One last thing. I cannot explain. It was bubbling coolant out around most of the perimeter of the head gasket (while cranking). I had the radiator cap loose, so I guess this was cylinder pressure. What is going on? I used a new felpro gasket (metal backed composite material, I put it on with the metal facing up towards the head, no sealant), and torqued the studs to 70ft-lb. I re-checked the studs and they still were at 70ft-lb last night.

I also noticed coolant weeping out of at least one of the head bolt holes.

I'll post some photos tonight.

So... any thoughts? :?

 

Did you use thread sealent on you studs that hold the head on? If not they will leak coolant. It also sounds to me like you took a lot of material off the block and head. check your points, and check your dist timming. My m38 wouldnt start when I first tried, the dist was no good, put a new one in and now it starts right up, well it did until my fuel pump died.

 

1. Yes, I used sealant on every single threaded bolt or stud that went into a coolant passage. I don't recall the name of the stuff, but it was a permatex product, something to the effect of high temp thread sealant. I used an entire tube during the engine assembly, so I'd hope I used enough of it.

2. Yes, I took a lot of material off of the block and head. There was a fair amount of pitting on the deck around the valves (burnt valve seats) and that's what it took to clean that up and to get both the head and block flat.

3. I'll start from square one and check the points and timing per the book and see what I find. I would think that if the points/distributor were fine before, they'd still be now about 6 months later. I was extremely careful when I set the timing a month or two ago, but who knows.... it could have gotten bumped I guess? The chain was pretty close to it when I was using the cherry picker.

I talked to the engine shop and they said that sometimes head gaskets will leak a little bit until you get the engine warmed up. Well, not that it's normal, but they've seen it happen before. They thought that maybe I should have put on somthing (high tac, or shellac?) on the metal side of the gasket. Is the felpro gasket that I used (composite with one side all metal) what everyone still uses these days? It came in the box of parts that came with my jeep. It still had the celophane on it and seemed to match the block, so I assumed it was a good gasket. I've got a second one still in the packaging at home. No instructions on it. I'm trying to find a number for felpro or federal mogul, but no luck so far. Their website doesn't seem to be working right.

 

Did you drain your carb before it sat? If not the could also be one problem.

 

Well.... I meant to run it dry, but I didn't. So instead (last october) after I pulled the carb I just pumped the throttle over and over until nothing more was squirting out. I opened the choke and throttle plate and gave it a good blast of brake cleaner before I bolted it down to the manifold a few days ago. Anything else I should do?

How do you know that your carb really is working right? I guess if you've got "more than enough" gas (flooded) you should see it on the plugs. And you should be able to smell it. I can give it throttle and hear the fuel squirt, but how do I know that the carb is actually working right?

Someone at work suggested I try an unlit, but open propane torch over the carb while cranking and see if that does anything. He said it used to work to get his stuborn Volvo to fire.... Any thoughts on that? I'd think propane would be pretty safe for the motor, safer than starting fluid anyway.

 

I've got a few photos and a few more thoughts. I have to wait until thursday before I can actually try anything out.

I got my wire harness today www.ez2wire.com) and they talk about the ballast resistor. It says to wire this so it only operates when running, but to bypass it when starting. Well that would certainly help out the spark, I'll try it.

Next thing, I found this photo of my distributor from pre tear down. I'm going to exactly replicate this and see if it helps anything. (posted for reference so I can look it up on the web over at the garage



Here's a few other photos for reference.

It looks like my pistons protrude about .007" to .009" above the deck (more than I remember, but this photo can't lie). I guess it's a little late to do anything about it, but if anyone has some experience they'd like to share (before I ruin anything) would appreciate hearing it. I'm going to guess that with the headgasket thickness I'm going to be okay, but would like to hear from others on this one.





Here's a photo of the shortblock. You can see the sealant on the studs... what else can I do?? The one with the red arrow was the most noticeable leaker.


And a photo with the headgasket on. Notice the metal backing (this side only, the other side looks 'normal'). Is this common? Should I have used a sealant on this or just gotten a newer gasket (or are all of the readily available ones the same as mine?)



Here's a photo prior to my first attempt at starting. Notice my fancy red engine analyzer laying on the transmission (right next to my oil pressure gauge zip tied to the shifter). Maybe it's a good thing it doesn't run, I can just see myself driving this mess around the block, falling off and getting run over

 

If I remember my m38 engines right the pistons where pretty close to the top of the deck. I know I have been told you cant deck the engines very much. If I was you I would rebuild the dist, and the carb, wont cost you much.

 

Bill, can you remember if your head gasket looked like mine or not (and if it did, did you have to use anything on it, or just put it on dry?).

I plan to rebuild the carb and convert the dist to an electronic pickup. I haven't done it yet, because I thought using proven/working parts would make it easier to get it running (less variables). I guess I was wrong...

 

i dont like a felpro head gasket period,mine leaked on my l head when first installed,it did finally seal,put it on dry also, i honestley believe if i had sprayed it down with permetex high tac it wouldnt have leaked,sounds like a lean misfire to me,or a bit out of time,try a teaspoon full of gas down the carb and see what happens,if you get too much worst thing that could happen is get it flooded,or a major backfire through the carb if its out of time

 

when i worked at a fork lift repair shop in the early 1970s, we would spray paint on the head and block before putting on the head gasket and never had any leaks.this was done on waukesha flat heads, allis chalmers ohvs and continental flat heads.i even did it on my own f134 i built in the early 90s and it has never leaked.we used just regular spray paint. just a light coat.

 

Any other head gaskets you'd recommend? Do they make thicker ones that fit the L134? (I've heard of using thicker/thinner head gaskets on other engines to make small adjustments to the compression ratio)

The package that the gasket came in had absolutely no instructions inside or out, front or back. Just a part number and felpro logo.

I can't remember the valve lash settings off hand since I did it back in January, but I know I set them .001" tighter than the spec in my manual (thinking that they may loosen up a touch as they seat). This adjustment was (obviously) done cold. My cam card actually had a different set of numbers on it, .010/.012 (I/E) hot. I thought I'd adjust to that later once it was broken in, especially since I have no idea how much a hot motor changes the lash vs a cold motor. I can't honestly understand why they specify different numbers, but they may have a reason.

 

I used a different type of head gasket, came with the complete rebuilt kit that jeepdoc sells.

 

It sounds like a timing issue. The first engine I ever built, I had the distributor in 180* off, and all it would do is sputter and backfire through the carb. I flipped it around, and it ran like a champ. I'll bet a dollar the problem is somewhere in the timing/valves/firing order.

 

victor,napa is about the only place that i can find them, different #'s = expanson the exaust valve gets hotter than the intake and therfore will expand more,and if anything on valve adjustment you should have went loose about a .001 as the valve seats it will close the clearence,but not alot

 

Good news. It's alive!

I rechecked the wiring on the coil/distributor and found that it was a little flaky. Sometimes my meter showed continuity, sometimes it didn't. So I pull the wires and put new ends on them, sanded down all of the contacts really well (until they were bright shiny brass), put a dab of dielectric grease on all of them and then I had good continuity with the meter.

I also aligator clipped in a bypass around my ballast resistor, so it was easy to unplug in the event that the engine did run.

I also flopped the dist around 180, but then re-wired the cap 180 (net effect should be 0 change--At TDC compression, the rotor still pointed at the #1 plug wire) just so it exactly matched the photo on the previous page... I don't know, I could have adjusted it 5-10 degrees maybe, maybe not, I don't know. It's really hard to eyeball the exact location of the rotor to the dist housing since they are a 1/2" apart. While it was apart I sanded down all the contacts and rotor with emery cloth as well.

I rolled it back out of the garage, hooked up the battery, cranked it over maybe twice and then it fired and ran. ..... :driving: After hooking up my meter I set the idle at 2000rpm for cam break in, did that for 20 minutes. No apparent coolant leaks today.... maybe that sealant needed some heat for it to start working?? I have no idea. So next thing is to retorque the head bolts, re-set the valve lash and change the oil/filter.

For the tappet clearance, my manual says .016" I/E COLD my cam card says .010/.012 HOT. Any thoughts on what I should set it at cold? (I mean, is there a rule of thumb for how much it will change between hot and cold running?) Set at .015 I/E cold I could hear the tappets. They were quieter than a typical toyota pickup 22R (if that means anything to anybody), but you could hear them clearly enough. I'm not sure what normal is.



Video (about 3.3MB)

Thanks for the help/comments guys. Just having a place to write something down and air your thoughts out can really help.

 

sounds good