51 B3B build thread - after all these years

[Merle Coggins]

Your hole over #6 is probably plugged with carbon and/or rust. You can usually poke around in there a bit and get it opened up. Try a drill bit, by hand, or pick away at it with an awl. 

 

On your pulley marks, I recommend only marking/highlighting the TDC mark and possibly the one where you want to set your timing. It’ll make it easier to see what you want with the timing light. 

 

 

[bkahler]

2 hours ago, Merle Coggins said:

Your hole over #6 is probably plugged with carbon and/or rust. You can usually poke around in there a bit and get it opened up. Try a drill bit, by hand, or pick away at it with an awl. 

 

It's steel at the bottom of the hole.  I scraped it with an awl and it left a shiney scratch and it sounds like metal.  If I get time this week I'll pull the plug again and see if I gave up to soon.

 

 

Quote

On your pulley marks, I recommend only marking/highlighting the TDC mark and possibly the one where you want to set your timing. It’ll make it easier to see what you want with the timing light. 

 

 

 

Those marks were just with a sharpie so I could see them better while trying to figure them out.  I've already wiped them off.   Sometime in the next few weeks I'll mark a couple of them with some black paint.

 

Edited December 30, 2019 by bkahler

[DJ194950]

18 minutes ago, bkahler said:

It's steel at the bottom of the hole.  I scraped it with an awl and it left a shiney scratch and it sounds like metal.  If I get time this week I'll pull the plug again and see if I gave up to soon.

 

I had to take a punch with a flat end in the hole and tap in the hole with a hammer-gently- took about 6 medium hits to get it cleared out. Then a ran a pipe tap down the hole with thick axle grease on the tap and took my time and chased the threads by stopping several times to wipe the grease and junk off the tap, regrease the tap work, work further until done and wiped clean with a rag in the hole. All good.

Just watch the depth of the punch in the hole. There may be as little a 1/8" (guessing more, but) over the piston top. I guess the best bet would be to turn motor over until piston was down some but I did not any junk to get way down into the cylinder.

 

It's all fun isn't it!??

 

DJ

[bkahler]

15 minutes ago, DJ194950 said:

 

I had to take a punch with a flat end in the hole and tap in the hole with a hammer-gently- took about 6 medium hits to get it cleared out. Then a ran a pipe tap down the hole with thick axle grease on the tap and took my time and chased the threads by stopping several times to wipe the grease and junk off the tap, regrease the tap work, work further until done and wiped clean with a rag in the hole. All good.

Just watch the depth of the punch in the hole. There may be as little a 1/8" (guessing more, but) over the piston top. I guess the best bet would be to turn motor over until piston was down some but I did not any junk to get way down into the cylinder.

 

It's all fun isn't it!??

 

DJ

 

What is the actual diameter of the hole where it opens into the combustion chamber?

 

What is the probability of junk falling on to of the piston?  That worries me more than anything.

 

Brad

[JBNeal]

the hole diameter on the combustion chamber side of the head is about 3/16"...I drilled and tapped a hole in more than one exhaust manifold upstream of expensive turbochargers for temperature probes, each time I used the grease-on-the-drill-bit-and-tap trick...also had a telescoping magnet in very close proximity to catch any metal that went astray, as well as jabbing down in the hole and cleaning until I stopped pulling shavings out.  Since you can pull a spark plug out for more access to #6 cyl, you can also do this with a magnet to get any shavings.  You can wrap some tape, sticky side out, on the end of a stick and swab out the cylinder, even blast some compressed air in there to flush out any crud...

 

With reference to the pulley timing marks, I only used the TDC mark to estimate TDC, then verified TDC with piston location and valve operation, to set oil pumps and distributors.  Once that was squared away, I haven't really needed to look at the timing marks again...

[bkahler]

It sounds like the hole seems to get plugged relatively frequently.  Since my manifolds are currently off it would probably be relatively easy to continuously inject compressed air into one of the ports to force any debris back into my face instead of dropping into the cylinder bore.   Sounds like a good task for New Years day

 

Using tips found on the forum I got the oil pan installed with a new gasket.  I still need to replace all of the bolts but that's a minor task I'll deal with later. 

 

Brad

 

 

[bkahler]

Well curiosity got the best of me this evening.  I removed the plug over #6 cylinder and started poking around.  I did use compressed air blowing into the open intake valve and once I had break through I had a small stream of dust blowing back at me.  It probably took about 15 to 20 minutes of digging to what you see in the picture.  I'll spend a little more time scraping away the carbon tomorrow but after that I'll call it good.

 

Thanks all for the tips!

 

Brad

[Todd B]

I know very little of building an engine. But shouldn’t  your engine builder have cleaned that carbon and debris out?

[bkahler]

13 minutes ago, Todd B said:

I know very little of building an engine. But shouldn’t  your engine builder have cleaned that carbon and debris out?

 

Normally I would say yes but in this case the builder was a friend who specialized in building Chevy 454 dirt track race engines.  I'd say that was 99% of his business.  My guess is he had never see one of these engines before he tackled mine.

 

Having a plug into the combustion chamber is a rather odd feature and I guess it doesn't surprise me to much that he didn't do anything with it.  It doesn't really bother me, the rest of the engine build was very nicely done in my opinion.  I know he balanced the crank, rods, pistons and flywheel and in that area I'm certain he knew what he was doing!

 

Brad

 

 

 

[CO54]

Looks great!!! 

I do have a question about the plug that has been discussed on the left side of the #6 plug(cuz I missed something)?  I'm looking at my head and seeing the same plug, what's it's purpose?  Why does it need to removed, cleared etc?

 

[bkahler]

Ok, time to time to figure out what to do about my next delima.  I've been working through the issue of my driveshaft and yoke being of mixed heritage.  In order to confirm what I have will work I need to check for is the amount of travel in the rear suspension from full compression to full extension.  So the plan was to jack the rear of the truck in the air to let the axle hang down and measure full extension, that step is easy to do.  

 

Now I'm trying to figure out how to compress the suspension to the point the axle is touching the bump stop.  This is where I run into a couple of problems.  The first minor one is I don't have any bump stops!  I don't think my truck ever had the rebound stops on the frame, at least there were no signs of any when I tore the truck down.  I think even if I had bump stops on the frame the axle would never come close to them due to the overload springs that are on the truck.  There are bump stops installed that the overload springs contact so I'm guessing they negated the need for the bump stops on the frame.

 

My only thought is to remove the rear shackles which would allow the axle to travel upwards but that entails removing the u-bolts holding the springs to the axle so the axle can be moved sideways to clear the shackle once it's unscrewed.  That is a lot of work that I'd rather not have to do if I don't have to!

 

Any suggestions on how to compress the suspension to determine maximum compression?

 

As a side note, there is 7-3/4" from the top of the axle tube to the bottom of the frame.

 

By the way, Happy New Year everyone

 

Brad

 

[CO54]

Compress the rear end?

Redneck ideas get some serious ratchet straps going around the axle and frame, snug away, then put all the weight you can find in the shop on board or that welding/build table for your engine on it to compress till the shock appears to bottom out?  Grab kids, adults what ever to add as needed if not enough????

I'd look at Kaiserwillys.com or 4wd.com if I wanted to add bump stops to the frame, old CJ's , MB's, Trucks or Wagons. 

Edited January 1, 2020 by CO54

[bkahler]

19 minutes ago, CO54 said:

Looks great!!! 

I do have a question about the plug that has been discussed on the left side of the #6 plug(cuz I missed something)?  I'm looking at my head and seeing the same plug, what's it's purpose?  Why does it need to removed, cleared etc?

 

 

With the plug removed there is a hole about 3/16" in diameter that opens into the combustion chamber right above the piston.  When #1 piston is at TDC so is #6 piston.  When setting the timing you want the #1 piston to be at TDC with both the intake and exhaust valves closed.  This is the firing stroke and TDC is what everything is based on. 

 

So what Dodge did is put a hole in #6 that you can stick a rod down into and as you're rotating the crank to bring #1 & #6 to TDC, the rod will tell you when your at TDC as it will stop moving up and then start back down as you pass TDC.  The goal is to verify the pointer on your timing cover is pointing at the TDC mark on the crank pulley.  Once you've done this you will always know when you're at TDC and by verifying both valves are closed on #1 then you know it's the ignition stroke.  

 

Once TDC is established for #1 and both valves closed you install the oil pump such that the slot in the oil pump shaft is in the 1 & 7 o'clock position.  If you look at the first picture in post #200 you'll see the 1 & 7 position.  This orients the distributor correctly which is when the rotor is pointing towards #1 spark plug.  The second picture in post #200 shows the rotor.

 

I hope that didn't muddy the waters to much!

 

Brad

 

 

[bkahler]

15 minutes ago, CO54 said:

Compress the rear end?

Redneck ideas get some serious ratchet straps going around the axle and frame, snug away, then put all the weight you can find in the shop on board or that welding/build table for your engine on it to compress till the shock appears to bottom out?  Grab kids, adults what ever to add as needed if not enough????

I'd look at Kaiserwillys.com or 4wd.com if I wanted to add bump stops to the frame, old CJ's , MB's, Trucks or Wagons. 

 

I don't have any adults or kids around (unless I qualify as one or the other!) so I'd probably have to make due with my front end loader.

 

The ratchet strap idea might be a good start.  If I can find a warm enough day, cause I don't like the cold, I could probably roll the truck outside, use the front end loader on my tractor to apply downward force and then cinch the straps at that point.   I'd probably get mighty p'ed off if I scratched the paint at this point ?

 

 

 

 

[CO54]

Ok, you have a point.  Behave with the paint.....

Yeah, I forgot from previous pics that you have load bearing toys that can apply pressure both up and down. I agree with the front end loader option.

 

[JBNeal]

The driveshaft travel can be estimated by using some strings laid out on the frame and a plumb bob.  For this, a plumb bob can be made from a big hex nut with a string tied around it, located directly above the pinion yoke.  The axles travel vertically, so the pinion yoke travel can be approximated by a vertical line...the highest point of the pinion yoke can be calculated as approximately the centerline of the axle's distance from the frame.  The plumb bob string denoting the pinion yoke travel can be marked with an alligator clip to approximate the highest point the pinion yoke travels.  This point represents also the center of the u-joint; now a measurement can be made from the transmission yoke...this might be a method that doesn't require safety glasses or touch up paint 

[bkahler]

43 minutes ago, JBNeal said:

The driveshaft travel can be estimated by using some strings laid out on the frame and a plumb bob.  For this, a plumb bob can be made from a big hex nut with a string tied around it, located directly above the pinion yoke.  The axles travel vertically, so the pinion yoke travel can be approximated by a vertical line...the highest point of the pinion yoke can be calculated as approximately the centerline of the axle's distance from the frame.  The plumb bob string denoting the pinion yoke travel can be marked with an alligator clip to approximate the highest point the pinion yoke travels.  This point represents also the center of the u-joint; now a measurement can be made from the transmission yoke...this might be a method that doesn't require safety glasses or touch up paint 

 

As much as I'd like to try Eric's approach with the straps and my tractor your method does sound somewhat easier and a little less risky to life and limb ?

 

I'll see what results I come up with tomorrow.

 

Thanks,

 

Brad

[bkahler]

I used a modified version of Brian's approach.  I ended up suspending a framing square from above and inline with the centerline of the pinion shaft.  Then I calculated the point where the diff would be when it in the same horizontal plane as the transmission yoke (i.e. shortest driveshaft).  At this point the driveshaft ended up being slightly less than 1/2" shorter than if it wasn't compressed.  That length still leaves 1/2" of travel before the yoke could bottom out on the driveshaft.  

 

I then raised the frame of the truck until the wheels were off ground and took another measurement and it was 3/8" longer than when sitting with the wheels on the ground.  In this situation there is still about 2-1/2" of spline engagement between the yoke and the driveshaft.  

 

I feel pretty comfortable that the yoke and driveshaft combination that I have will work fine.  Time to buy the u-joints!

 

Thanks!

 

Brad

 

[bkahler]

I've got a question about the gasket between the transmission and the floor cover plate.  I bought the gasket from Roberts and it's advertised as going between the transmission and the floor cover.  The gasket itself is somewhat pliable but it's going to take some pressure and possibly some carving of the inner diameter to get it to fit.  

 

Anyone used this gasket before and made it work?

 

 

 

[JBNeal]

I believe the idea here is to bolt down the trans.panel to compress the gasket then cover with the floormat...it's more of a draft seal than a fluid seal so it just needs to fill all the gaps...you could probably bolt down that panel for a few days, then pull it to see how the transmission marked the gasket for trimming a little bit...

[bkahler]

3 minutes ago, JBNeal said:

I believe the idea here is to bolt down the trans.panel to compress the gasket then cover with the floormat...it's more of a draft seal than a fluid seal so it just needs to fill all the gaps...you could probably bolt down that panel for a few days, then pull it to see how the transmission marked the gasket for trimming a little bit...

 

That's kinda what I figured but it sure seems like it's going to need a whole lot of compression to get it to sit low enough.  I guess maybe I should start compressing it now so it will be down far enough when I'm actually ready to put the floor plates in!

 

Thanks,

 

Brad

 

[ggdad1951]

Never put one in....don't even notice

[JBNeal]

As thick as that foam is, it's probably a decent sound insulator so ya can really get on the throttle while on the road and not think that the engine is screaming...

 

When it's time to install them floorboards, there's those bolts clipped to the cab that sometimes get lost...I made a small modification that addresses missing or damaged bolts that might help...

[Merle Coggins]

That’s probably for a 3 speed. Yours looks like a 4 speed. I had some thick chunks of foam that I used to cut my own. Similar to that, but sized for my trans. 

[bkahler]

44 minutes ago, Merle Coggins said:

That’s probably for a 3 speed. Yours looks like a 4 speed. I had some thick chunks of foam that I used to cut my own. Similar to that, but sized for my trans. 

 

Correct, mine is a 4-speed.  I didn't think the 3-speed transmissions had any protrusions above the floor panels so what would the gasket be sealing?

 

At some point I saved this picture from somewhere and it shows foam, probably similar to your approach.

 

Brad