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Discussion Starter #301
Sort of curious where you got the bolts for the new setup. Those bolts are a special thread and extremely high grade. On the Cummins 4bt damper the only source I ever found for those was Cummins. Yours may actually be about the same length as those since you had that adapter on the front. Those 3924584 bolts are M12x1.25x60 mm flange head grade 12.9 or higher. Also probably one of the 2 places on the engine where red Loctite is recommended. The other is the flywheel bolts.
Charles, as far as the locktite I whole-heartedly agree that these two places are paramount to needing locktite. I ordered ARP flywheel bolts from Summit Racing. They come with a lubricant, which I believe is to achieve the correct torque. I was surprised because I thought the locktite would be its own lubrication while wet. Food for thought.
 

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Yeah, that's why I never found those extra fine thread bolts in the aftermarket. Cummins probably had those made just for the application. You have to be careful and be sure you have those torqued well. A little too loose and they will break. We had one guy break 3 of the 4 on his setup. Yours are even 10mm longer than the Cummins balancer bolts. You can find the grade 12.9 in socket head cap screws but not sure if anyone makes them in hex head.
 

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Discussion Starter #303 (Edited)
I could go Socket head with flat washers and be happy. Any sources? Also, I chose 70mm length after I looked at the original bolt which is 35mm in length. at least 30 mm went into the threaded portion of the crankshaft with the original pulley. Measuring the 50mm bolt I have I noticed that only 10mm would have met with the crankshaft internal threads. That is why I added 20mm to make 70mm length. It was to get the same amount of threads contacting inside the crankshaft as the original. The length was needed due to the spacer, tone ring, and barring tool thickness.
 

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For the socket heads, just do a net search for M12 x1.25 x 70mm 12.9 bolts. Heck, even Walmart lists them but only packs of 25 or more. I even found some regular hex heads on ebay but they aren't the flange head like Cummins uses. A company I've bought a good many bolts from is BoltMax in South Carolina. They sell the 70mm cap screws in a 10 pack for $14.02. Their shipping cost is pretty cheap as well. Their part # 532953
 

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I usually purchase bolts in quantity from McMaster-Carr. I've yet to receive Chinese crap bolts from them. They sell to industry where quality can be a matter of life or death. (I've been working in Chemical Manufacturing for 40 years)


The last purchase I made from them was in February this year. I purchased flanged head M6 x 1.0mm x 22mm long bolts - grade 10.9. I used them to stack a 6 rib pulley on top of the 8-rib fan drive pulley on my 1998 6BT for driving an air compressor.
 

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Yes, McMaster lists the 12.9 cap screws. They come in a pack of 10 for $14.67. Just a tad bit higher than BoltMax.
 

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Discussion Starter #308
Are the McMaster Cap Screws the same as the BoltMax? Same manufacturer? That is the issue with buying from an online establishment. Unless they tell you where something is made, you really don't know. Might be the same source.
 

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All the ones I've ever bought from BoltMax I think were made in USA. All the ones I got were a black oxide finish and not the zinc plated ones. They have stainless too but those don't have the strength factor. They do sell cheaper imported bolts as well but they are listed separately. Have never bought any from McMaster but used to have one of their catalogs on my desk where I worked. Back then they mainly sold to industrial customers and not individuals. There are super high grade import bolts out there, especially those coming out of Europe like the UK or Germany. Most of the imports we see these days are China and those can be good or not so good.
 

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Discussion Starter #310 (Edited)
I purchased the cap screws from BoltMax. No need to keep buying the same thing over and over. They come in a 10pack, however, I will only use four (I hope). Just an update... OIL PAN: you were right (char1355) on the oil pan. The pan was taken to a welding shop. Expecting back any day now. I am not disappointed that I tried to weld it but wish I had not in the end as it wasted too much time. The engine mounts are coming along fine but I have the engine on the engine stand perpendicular to the stand itself and is bolted to the bolt holes needed to test the second mount. Once the oil pan is bolted on I will continue. The mounts look good so far. I will take them to the welding shop once the fit-up and adjustments are correct.
 

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Discussion Starter #311
The oil pickup tube is welded and installed. I did leak test the oil tube as well. I put a piece of PVC with a cap over the suction screen and immediately found a leak on a weld. Rewelding was quick, and this time no leak. The pan was welded as well. I owe thanks to Johnpp77 and his thread: 85 Chevy 4x4 4bt 4l80E

Oil PIck Up Tube.jpg
Oil Pan Modified.jpg
Oil Pan Mod Oil Drain.jpg
 

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Discussion Starter #312 (Edited)
I was reading another thread, and the concern raised was the injection pump timing gear and the propensity to crack after prolonged use. So, I purchased another timing gear, which is supposed to be an upgrade. The only problem I encountered with the new Injection pump timing gear was the markings on the side. I had to hold the gear up to the light to be able to see the markings. Then I drew on the gear with a felt marker, so I didn't have to look for them on installation. I also noticed the barring tool (see picture) would not fit directly on the crankshaft as the guide (which is machined on the end of the crankshaft) is too long to fit into the barring tool I put the original crankshaft pulley on and it was still too long for the barring tool. I ended up putting my spacer on before the barring tool to make it work. I retimed the injection pump. It as 1.15mm after the new Inj pump gear install. Specification is 1.66.
Old Inj Pump Gear Coming Off.jpg
New Inj Gear Markings Hard to Read.jpg
New Inj Pump Gear Markings.jpg
Spacer needed with New Barring Tool.jpg
 

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Never seen a baring tool like that. The ones that Cummins sells are the type that go in a port and engage the flywheel. Nothing wrong with that design so long as it fits properly. Would be handy to torque a pump gear for a P pump.
 

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Never seen a baring tool like that. The ones that Cummins sells are the type that go in a port and engage the flywheel. Nothing wrong with that design so long as it fits properly. Would be handy to torque a pump gear for a P pump.
It's made by Fleece. I have one on my 12 valve. It's also handy for adjusting valves.
 

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Discussion Starter #315
Yes, it's called a Fleece Barring tool. I picked it up on Amazon. It is very handy, however, an adjustment is needed if you purchase one for a 4bt with a stock crankshaft pulley. It appears the hole on the back side is shallow and the protrusion of the crankshaft is (Maybe) 1/8 inch too much. I have it in the picture with the adapter I had made for the tone ring. I used it to re-time the injection pump after I changed the Injection Pump Gear. Installed the front seal and sealed the front cover as well today. With the new adapter plate, this was my only option for a barring tool.
 

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Discussion Starter #316 (Edited)
Installed the front cover yesterday and put the new Pulley-Tone Ring- Fleece Barring tool on today. I am waiting for the washers to come in for the cap screws since I cannot find a 12.9 strength flange bolt (70mm in length). I like the way it looks. I still need to make a bracket to hold the sensor for the tone ring.

Pulley-Tone Ring-Fleece Barring Tool.jpg
Pulley-Tone Ring-Barring Tool 2.jpg
 

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Discussion Starter #318
Yes, it is there to stay with the exception to the washers I ordered for the capscrews. Once those come in, I will torque it down. I would have liked to put the tone ring behind the pulley, but it would not fit. As it is, I have a spacer behind the tone ring (talked about in an earlier post). It should work out. Fingers crossed.
 
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