Builds Family haulin' (5 Viewers)

[cruisermatt]

I hear you on the fluids, cost adds up quick when you have to keep draining and re-filling, not to mention having to spend the time containing and disposing all of it.

Links will be 1/8" wall 1/2" tube and shifters will be 1/2" solid stock, pretty normal I'm gathering.

 

[Tapage]

damn Mike .. and you are still loyal to your 4bt ...

 

[1974FJ]

Also noticed some cracks in the flexplate. Not good.

.

Good move, those things will crack. what was the part number for the cummins plate you ordered? i bought a used one when mine broke. generally ive always heard that the wave-ring would fail before the plate.....guess not.

 

[boots4]

@1974FJ, I'll find the receipt and post up the part number for the GM/Cummins flexplate.

 

[boots4]

Played with the Torque converter to flexplate spacing. I had a total distance of .200" between the flexplate and the torque converter feet and I had put in .085" thick washers for spacing. The generally accepted spacing is .060" to .187" so I was within that range. For experimentation I grabbed some thick .120" washers to place my gap at .080". Noise is still there.

Ran it with my cross under exhaust piece on and off wondering if it was just rattling on something. Noise still there.

I fashioned a mechanical oil pressure gauge, bolted it in a port, and took a quick reading. I got 64psi at cold idle and as I reved the engine the oil pressure increased appropriately.

Looks like I'll be getting my shop ready to pull the engine again next week. Starting to consider a spun bearing but it could be something with the flexplate I cannot see with the tranny and engine hooked together. Well, at least I'm getting faster at getting that engine out.

 

[boots4]

@1974FJ

Part number for the Cummins/GM flexplate is 3918957

 

[boots4]

Yup, pulled the engine again. Enlisted the wife's helping hands when needed. Pulled apart the flexplate assembly to see what I couldn't see.

I thought painting parts may have gotten in the way of a flush fit so I started cleaning off paint from the mounting surfaces and found the surface of the crankshaft flexplate hub to not be so flat. You can see the shiny part is the surface that was contacting the back of the flexplate. In fact it may have been part of the reason why my last flexplate cracked the way it did. My close source with a lathe was out of town so I backyard-milled it. I put a sanding disk on my angle grinder and smoothed out the surface. I checked with a caliper to get it even all the way around and worked the high spots to match the low spots. It's not perfect but it's definitely better than what I started with.

Next I noticed the backside of this hub had an indentation near one of the bolt holes (12 o'clock on the below pic).

There was matching metal debris on the surface of the crankshaft. I figure this did not let the hub sit flat against the surface of the crankshaft and caused some wobble in the flexplate/torque converter assembly.

I grabbed a fine file and carefully smoothed off that debris. I sanded the surface after I removed that debris. I also replaced the main seal one more time just in case to eliminate it from being the cause of having to pull the engine in the near future.

I removed the tranny adapter and cleaned out the threads in all the bolt holes that hold it to the block. I sanded the block surface and the adapter surface to remove any dings or potential debris. I then installed the adapter back on and looked for flexplate contact. I did find some new marks. The starter ring looks like it was just slightly contacting the adapter. In the pic below just to the left of the two large bolt heads there is a machined groove. In the center of that groove, the streak, was one set of contact points.

At the bottom of the adapter is another set of contact points. Not all the these points at the bottom are from this round of contact, I had previous contact at some point before I owned this engine when the #4 thrust bearing on the crankshaft failed. The top marks were from the wave ring's bolt heads and the bottom marks were from the starter gear ring. In this round you can see the streak that look darker or dirty and this is the second contact points I was getting. This contact was making the loud "engine" noise I was hearing. With the new flexplate being flat that reduced the clearance behind it and the adapter plate so once things settled out (I'm guessing heat cycling of the assembly and the torque converter) there was no clearance. Plus I found evidence above that the assembly may not have been perfectly flush causing a wobble and that wobble contacting the adapter.

To give myself a more clearance I cut the grooves in both places a little deeper. I did this with my trusty angle grinder.

I inspected the flexplate and wave ring and found no issues. I wanted to build a stronger wave ring (spaces the flexplate and the torque converter mounting points) but I was not able to find someone who could cut out some precision parts I needed to build one the weekend I had time to do all this work so I ended up reusing my wave ring. Cummins wanted a ridiculous amount for a new one (they call it a torque converter adapter) which also drove me to reusing the one I have. I assembled all parts about 180 degrees from last time in attempts to better balance the system.

While the engine was out I found a brake line going to the front circuit getting smashed so I fixed that. I also found the plugs on my fuel pre-filter head , the ones I wasn't using, to be loose. I'm pretty sure I was drawing air into the injection system because of this so I fixed those too. There were times after a hard acceleration and a quick release of the throttle that the engine would die and the injectors would require re-bleeding to get the engine fired up again. I checked everything on the injection pump but couldn't figure out where the air was getting in, this was it.

Once it was all back together and after that nervous first start to see if the noise was gone all was well and that loud noise was gone. Now it's just normal obnoxious cummins noise . It was a head scratcher why it took a week for that noise to show up but I was glad that all the work made it go away.

We headed to the coast last weekend pulling the trailer with bikes for some camping and riding. It did seem to run a little warm, averaged 205F, but I never got over 220F on the hill climbs. Probably have some bubbles in the system still. I did moderate on the hills because I noticed my hose on the small turbo's outlet starting to degrade so I keep boost below 40psi on the hill climbs. I have a fix for that I just haven't done yet; I need to order a part to finish it. Anyways, it's great to have it on the road again and enjoying that diesel torque. I'm hoping to get back to working on my rear storage drawers and wiring for my fridge.

 

[GLTHFJ60]

Fine work sir

Your experience makes me want to pull the engine out of my 60 just to check up on things!!

 

[boots4]

Thanks Johnny, if I had a concrete pad to work on it would be much easier... Someday.

 

[FF LC FREAK]

Now that it's all back together, let me know if you need a hand.

Seriously, though, my schedule opens back up in October (back down to just 1 full time job) if you ever need an extra hand.

 

[GLTHFJ60]

Thanks Johnny, if I had a concrete pad to work on it would be much easier... Someday.

All the concrete did in my scenario was attract other trucks!! Now there's even less time to work on Moonshine

 

[Tapage]

Funny thing you said, taking easy on the boost .. under 40 PSI .. ( mind set on Toyota engine boost )

 

[boots4]

Let's see, it's been a while but here are a series of things I've been doing to the rig over that last 6 months not necessarily in chronological order. Photo posting had changed since I last played around from my hosting service but I think I got it figured out. NOTE: Might not have it figured out yet. I'll try a couple more things if the photo's don't show up.

With pulling the flexplate a couple of times I was pulling the starter in and out too. One day the truck wouldn't start, it just made a electrical spinning noise on my wife. Luckily she was at home and not stuck somewhere else. When I got home I checked it out and found that the starter was hanging on by just the lower bolt. When I pulled it out I saw that the top bolt had pulled out, but not all the way, which resulted in the top ear on the starter breaking. With this being a gear reduction starter to turn over the diesel it sees some torque. I went through some research and found something that said it fit my application but didn't which I returned and eventually found one that would work. During that time I generously JB welded the ear on my old starter back on (I'm not set up for aluminum nor did I find anyone at the time to weld it up) and fixed the trashed threads on the top hole (actually just tapped both holes for larger bolts to keep them the same) and ran it for a week or two while I sorted out the starters. You can see the top ear "fixed" in the below pic on the old starter. Once I finally got a starter that would fit (so I thought) I began the swap only to find that the nose around the gear on the new starter interfered with the opening on my tranny adapter. You can see the difference in the pic below of the new one on the left and the old one on the right.

In comparison the other difference is that there is an additional grounding post on the new starter that isn't on my old one. I don't have anything hooked up to this post and it works fine.

Old starter nose. Also notice the wear on the teeth and I'll come back to that.

Here is the new one. Note the difference on the teeth from the old starter.

It didn't fit... So I backyard machined it with my angle grinder until it did. I took measurements on the old one and ground down the new one until it was the same. Now it fit.

Except there was the difference in the teeth. After several starts and then no starts (starter didn't turn over at all) and a week or two of more head scratches I finally figured out it was the depth of these teeth. The old starter with the old and new flexplate worked fine because the starter teeth had previously clearanced. With the new flexplate not being bowed like the old one that placed the ring gear closer to the adapter and caused ugly noise plus it also meant the distance between that ring gear and the starter teeth was tighter. The new starter's teeth were two deep and as that starter gear rotated to slip into the teeth on the flexplate they would not mesh and get stuck effectively head bunting the ring gear. At least on this starter when the solenoid activates it does two things: 1, it slides this starter gear rotating it as it goes to engage with the flexplate gear and 2, at the end of its travel connects the power from the battery to the starter motor. Since this starter gear wasn't traveling its full distance that battery to starter motor connection wasn't happening and so the starter wouldn't even spin. Yeah, this took me a several in and outs of the starter to figure out what was going on since sometimes it would start and other times it wouldn't even turn over. I took the starter apart, compared it to my old one, tried different grounding points because the new one had that additional grounding post and finally ended up clearancing the teeth on the new starter gear with some finesse on the angle grinder. With enough clearance to match the old starter gear it's been performing flawlessly ever since.

 

[boots4]

My front freeze plug started leaking. At least this time I didn't have to remove the engine but I did pull the cooling stack out so I'd have unrestricted access to reset the plug. The plug is under the center pulley that was once where the mechanical fan was attached. After getting that taken care of I also exercised my lifetime replacement on the alternator. The front bearing was squealing and they exchanged it with no issues. With the open access I played around with the spacing on the alternator pulley via washers for spacers and made some improvements. Nothing's been squealing since.

While I was there I replaced my water pump thinking that it had been contributing to the squealing I was having. I researched and decided to try out a newer model pump made for the 6.7 engines. Old on the left has 5 blades, new on the right has 7 blades. I wanted more cooling for the summer months so I'm trying this out. It did drop my temps by 5 degrees.

 

[Kief]

Do you get more heat issues as a result of the increased boost/fuel and increased HP or is the intercooler heating up the radiator thatuch more? Have you any estimate of HP?

 

[GLTHFJ60]

I've never felt the need for more cooling. Nice!!

 

[boots4]

Do you get more heat issues as a result of the increased boost/fuel and increased HP or is the intercooler heating up the radiator that much more? Have you any estimate of HP?

I do get more heat from increased boost/fuel mods but I don't believe that's the only factor. After I did the compounds I did notice that the intercooler is doing it's job by touching the intake and outlet tracks and noting that the outlet is much cooler. I didn't feel as big a difference with a single turbo. So that's more heat getting into the cooling stack (radiator is next after my intercooler). The other factor is that I'm sucking in under hood air temps into my air filter. I'm trying to figure out a way to pull in outside air like a snorkel but not using a snorkel, more Humvee like, but I'm not finding a perfect path for the tubing and placement for the intake above the hood yet. I think a snorkel might be too restrictive for a pair of hungry turbos, at least the current offerings. I read someone's experimentation on true cool air intake setup on a duramax and he noted reduced/stable coolant temps and increased power differences when he had a true cool air intake set up and wasn't pulling under hood air into his engine. Since my intake is on my exhaust side and it pulls mostly from under hood I think it gets warmer on that side and then it's a cycle of ingesting warmer and warmer air adding to an increased cooling strain. I might even try some hood vents. That will help get the heat out from under hood but hot air will still enter under hood via the hot cooling stack so it probably won't be the improvement I'm hoping for. This is project I've been thinking about lately but not worried about during the winter months.

 

[The Phoenician]

The snorkel is restrictive for one turbo, so it will be too restrictive for two. When I removed the top of the airbox my boost was able to go from 14 to nearly 30 psi when I floor it. When I get back from deplyment, and get the compounds on there, I'm thinking of a hood scoop or an opening in front of where the air box will be. I have to figure out how not to get rain water sucked in, but that's a problem for next year.

 

[boots4]

I'd like to do some kind of Humvee hat above the hood that I can remove and put an extension on if I ever needed to go into deep water; emergency bug-out stuff. Also thinking about water collection issues.

 

[Kief]

Hmmm, I plumbed into my stock fender air box in my 80 bit used a different filter housing, I wonder if it's restricting my intake flow. Good point on the snorkel. I'm not used to considering how diesels are effected by airflow/exhaust restrictions.