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Discussion Starter #1
As many of you know I have been working on my motor now for over 1 yr , as I have had many problems and thanks to the good men on this forum and their good advice, avoided many more ! The last you heard I had discovered mismatched pistons , so needed a new one of proper weight. As I had previously posted and some read , we found (1) at -Agkits . Com and their support is Reliance power tech support The man we spoke with was Kevin Borkowski, he was very helpful. shipped to wife's sis in Florida, wife brought back with her , along with a new water pump for our 2007 GMC , AND as I had asked previously are these rebuildable? I was able to balance to - 1 gm. As it had been some time time since disassembly I decided to wash all parts,(even though all had been in labeled plastic bags ).When washing the assembly lube of the rod bearings, discovered imbedded grinding stone particles, checking the crank,scratchest there also, check mains,similar! Was I ever hot:pissed: Took all back to the shop, first they tried to say it was dust from the air, then it was not their responsibility to see that the motor was clean,but polished the crank. When I inspected it (still at the shop) still saw scratches & nicks, I said no this needs reground, which they did NC .and of course new set of .010 over bearings NOW The original main plastigage clearance was .003 it's now .004 (spec .0019-.0045) regrind at .005!! Rods were .003 / now 1&4=.0028 / 2&3=.0038, spec max, .0045 & above must replace!
You will remember in turning crank by hand had , tight & loose 90% apart , that went away. Hallelujah at least for that . Before each ass - I had washed with air sprayed varsol, this time I used 1/2 gal of thinner on & in all holes of block & crank, also 1/2 gal or so of varsol from each way possible , the garbage was UNBELIEVABLE!! I could not make the cyl bores feel clean until I used a cyl hone while spaying varsol.

But I have these questions, if anyone knows what they are, I just discovered these RINGS and don't remember taking them out, or putting in new ones! The two square-ish ones look new, the round oval looks used. IMG_4263.JPG these are all rubber and this one the shape is rectangular, approx 3/16 thick x 3/8 high x 3 1/4 wide IMG_4264.JPG this one is oval shape, approx 1/4" x 3/16 x 3 3/4 IMG_4265.jpg this is rectangular shaped 1/8" thick x 5/16 high x 6 5/8 wide.
 

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Oil fill/cap gasket on gear housing cover, valve cover oil cap, coolant inlet, the thermostat outlet has a stepped square oring, water pump and the oil fill on dr side of block are the only ones Im aware of. That big oring may be for a SAE flywheel housing in a marine application. There was a 2 bolt rear core plug coolant supply that used a square oring as well but it was in busses and med duty mostly.
 
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Discussion Starter #3 (Edited)
Thanks RED. I had considered the lower rad hose, also the w pump,I believe the #2 pic from above message is the w pump (gasket o-ring seal ) we did take photo of lower radiator hose inlet (inside) and found that there is a gasket there. below are additional pics. O-rings.jpg housing torque converter info. IMG_4281.jpg the thermostat seal, IMG_4279.jpg the oil fill plug.
The #47 is a1/8 X1/8 seal,. I did not have a new one , so I squeezed a little silicone into its groove (more to insure it stayed in place) pressed in the rubber, wiped off the excess and quickly bolted together, with new #50 seal installed
MY PROBLEM is --- I have assembled & disassembled so many times, it is hard to remember what I did when!
 

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Discussion Starter #4 (Edited)
Progression pictures of rebuild

Here are some shots my wife took along the way.
#1 Me installing one of the many hydraulic hoses
#2sitting on the stand before putting in backhoe?
#3getting it into the backhoe and needing counterbalance to keep it there and not on my wife who was helping.
#4squeezing it in and we had to really work and tip it at a 30 degree angle to get it in without scraping and denting the oil pan.
#5 McGiever at work, the neg jumper connection by the starter. The heat shield behind the exhaust manifold and one by the oil supply line for the turbo.
#6 I thought this would be a good idea for finding the fuel pump timing pin hole. If the timing pin sticks in the hold loosen torque screw so you can pull the pin back out without breaking it.

Hope these come out so you don't have to crank your neck to much. Can not figure out how to flip them on this forum.

My wife does have a sense of humor....
#1 IMG_4246.jpg
#2 IMG_4215.jpg
#3 IMG_4249.jpg
#4 IMG_4250.jpg
#5 IMG_4278.jpg
#6 IMG_4283.jpg
 

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Discussion Starter #6
In regards to the barring tool that had been discussed under water passages some time ago. We purchased the SP tools part #95650A. We had less than 3/16 inch in the length and 1/16 of side engagement. I had the shop add 1/2 inch to the length and diameter of 1.161 as in the original condition the tool was useless. I added .010 to the diameter of the collar, by soldering on a .005 brass shim. Even with the added length and diameter to the gear I get about a quarter turn out of my ratchet and the teeth jump. Even with the modifications the tool is barely useable.
image.jpg
 

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Discussion Starter #7 (Edited)
I don't know what happened here !, I had made a reply to Char that does not now show! So let's try again!
*Thank you so much Char, you always do your best, going out of your way trying to help anyone & everyone. You are correct in that my machine is CASE , but Case 580k backhoe 1989 . We have the down loaded Case repair manual, and my wife accessed the parts manual online, that is where she got the picture of the torque converter housing cover & its pump, without PTO which is what I have! I replaced seal #50 & reused O ring &47, it's rubber is about 1/8 X1/8, putting a small bead of silicone in its groove , pressed in O ring wiped of excess with finger and quickly bolted up, so that is all good! There are two sq bosses on#48area that go into the output tube of the torque converter that has 2 notches, when replacing #50 seal it only presses in 1/2 way if you do more the seal surface will NOT clear the notches!
As for the above pictures, wife took them with her cell and down loaded to my iPad, looking at them in the picture file looked great but when attached in message they turned,and we don't know how to fix,I apologize sorry , THANKS,AGAIN
Robert
 

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Discussion Starter #8 (Edited)
Advice and thoughts are needed

This is to do with my rebuild of the 4bt390 in my Case 580K backhoe. As you know if you have followed me over the last year, I have had my problems with this rebuild. I have the engine in the backhoe and ready to start it. It will not even fire! I have checked the fuel injector pump and the timing and it is correct. I have now taken the front off the motor to show the timing gears and they all line up, per everything I have read.
I am at wits end trying to figure this out. I really could use some advice here on what you might think the problem is. When cranking the motor it seems to me that one cylinder the compression is coming back into the intake manifold as well as the exhaust manifold.
Posting a few pictures so you can see the gears and give me your thoughts. Really appreciate the help.
Robert
IMG_0211.jpg IMG_0215.jpg IMG_0214.jpg IMG_0212.jpg
 

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One thing you mention should not be happening. There should be no positive pressure into the intake manifold area from the cylinders. That should be suction only and have positive pressure only from the turbo when running. About the only way I think that could happen is if the valves are not properly adjusted and an intake is hanging open on compression cycle or you have a broken camshaft. Take the valve covers off and be sure all the valves are moving correctly. Might double check the valve adjustment. Have you verified that you're getting fuel to the injectors? If the start/stop solenoid on the injection pump is not working there would be no fuel coming to the injectors. If you are getting fuel and it is kind of weak then there's probably air in the system. It takes a lot of pressure to fire the injector. If you crack a nut on an injector while spinning it over the fuel might hit the ceiling. Be careful. That stuff can be dangerous. Keep your body parts clear. You can squirt a little starting fluid into the intake to see if it kicks over. Won't hurt as long as you don't go nuts with the stuff. Actually, Case had starting fluid systems on equipment like yours. You've checked the pump timing so that is pretty much ruled out. One thing I was wondering. You mention this is a 580K backhoe. The only ones I find in the Case catalog are a 580CK and 580SK. The 580SK came with a 390T engine with the CAV injection pump. Is that what you have?
 

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Discussion Starter #10 (Edited)
Thanks Charley , for your quick reply ! To answer your Q about ck, sk, no it is a 580 k , 1989/1990 with a 390 T ,by my manual. The engine needed bored & sleeved , the crank polished, new bearings, both block & head decked, cam was good, block cam areas were at max so bored and pressed in bearings , head all new valves and seats. However they did not clean the block & head properly so when I took it apart (again) to see why I was getting that tight,loose every 90* I discovered my bearings were impregnated with grinding stone & the crank was scored. They polished the crank but still had big score marks , so had them grind 10 under, before I had +~.003 on all now I have .003 front & rear, .004 on the rest . This time I power washed both the crank & block using 1 gal varsol then 1/2gal lacquer thinner , wow the junk, even had to use my cyl hone in the sleeves while spaying in solvent to make them feel right (get the grit out)
With the gears lined up as you see in the pics #1 piston tdc intake 10 , #2 ntake 10 , 1&3 exhaust 20 THEN rotate 180*
, intake 3&4 .010 , exhaust 2&4 20 . I bought a new lift pump 2 yrs ago I used the hand primer, bleeding at the filters then the inj pump, clear fuel, removed the the 4 lines, cranked over , (with a battery charger jump start & the pickup , fast at first then boged down) but the fuel only squirted out about 1/2" . Have not tried either because of the way it cranks &the poof back both in the intake & exhaust
I had washed the block & head before also but not so axtensivly . Now that the crank has been ground that tight, loose went away .
 

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Fuel barely squirting sounds like air in the system. That stuff should almost spray as a fog when the injection pump is at full pressure. Sometimes takes some time to get the air out. However, you still shouldn't have any backward pressure in the intake. Sounds like an intake valve leaking.
 

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Discussion Starter #12
Thanks again Charlie, also wanted to add this with a question. When I was having problems 2 yrs ago, I noticed that the front gear housing was heavily siliconed & leaking oil when I cleaned it off I saw that it was broken so I built a hold down clamp, cleaned all real good & plastic epoxied all together, so in the rebuild I had it welded. When we took the cover off we discovered that the cam gear had a broken tooth so I had them replace it. When the new one came in I checked it, looked the same, same size, same number of teeth, & pin hole in rear,
Question, is it possible that the pin hole is in a diff place, in relation to the key slot & the zero stamp marks, at the teeth, are the 4 cyl & the 6 cyl cam gears diff ?
 

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4bt & 6bt use the same cam gear, so timing hole will be the same.
 
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Discussion Starter #14 (Edited)
Today I removed inj #1 and had my wife hold a small steel rod down the hole, while I used the barring tool to turn the motor, established that #1 was indeed tdc with all the gears properly aligned, & #1 rockers & valves also proper.010 & .020.
So now it's test the valve springs and possibly replace
 

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Valve springs are seldom replaced on a stock engine unless higher performance is desired. If a valve is hanging open it may likely get bent since there is very small clearance between valves and pistons. When you had the engine apart did all the valves look to be straight? Don't guess you could have a seat insert that has come loose.
 

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Discussion Starter #16
Thank you, Thankyou! Yes I could, the shop replaced all valves, but I don't know about the seats. Looks like the head comes of again! So new gaskets, head & intake, DARN
 

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Thank you, Thankyou! Yes I could, the shop replaced all valves, but I don't know about the seats. Looks like the head comes of again! So new gaskets, head & intake, DARN
before you pull the head, take off all the rockers and injectors. blow air into the injector holes one at a time with a long extension and rubber tip to seal the bottom of the injector holes, and see if air comes out the intake manifold or exhaust pipe. if NO air comes out of the intake manifold or exhaust pipe, there`s nothing wrong with the valves or seats. might save the replacement of a perfectly good gasket. that would be my last test before removing the head.
 

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Yes, that's a very good idea. Don't want to trash a head gasket unless you just have to. You mentioned you verified that #1 cylinder is coming to TDC and those valves were in proper adjustment. Did you check the adjustment on the other 3 sets of valves? Only takes one intake valve to release a lot of pressure into the intake plenum. Another check you could do is a compression test on each cylinder if you had the tools. That would also tell you if a cylinder wasn't sealing properly. The air hose test will work just as well to tell you if there's an open intake when it should be closed. Another simple test would be tape a loose plastic bag over the intake and bar the engine over. If the bag starts to inflate you know that there is a leak.
 

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Discussion Starter #19
Well, , I followed the , remove the injectors, use rubber tip blow gun, 130 psi air each hole, my helper said he could not detect any air coming in the turbo exhaust, #2 cyl blew back hard into the intake and would build NO pressure!! So I pulled the head, all the NEW valves look perfect however I saw a little something alongside the #2 intake, used a small screwdriver to remove, it was aluminum from the partially melted piston, so it looks like they did not even grind the seats, I will take it in tomorrow and stay with it , to see what they are going to do & what line they are going to ,, try and give me !
Charlie you asked about the valve adj on the other 3cyl ? I assembled engine & did the valve lash but did check anyway & they were correct
I thank y'all for all your help, I would have been lost without it
 

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That little bit of scrap metal is all it would take to keep the valve open. That would also mean the adjustment on that one was off. Can't believe a shop would install new valves and not check the seats. You're lucky it was only open just a crack. Otherwise, it could have damaged a piston, bent a valve, or bent a push rod. Frankly, they owe you a new head gasket.
 
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