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Discussion Starter #1 (Edited)
This is only a suggestion for the newer folks with limited Cummins engine exposure and pertains to doing multiple engine repairs to a running engine and ending up with an engine that will not start.

The first thing you should do is a test run of your engine immediately after your purchase. Test runs should be limited to no more than a 30 second run without coolant. This does not mean run 30 seconds and shut off and immediately restart. The early engines with the 9 mm injectors have enough head failure problems with head cracking in the injector to valve seat area without any additional encouragement. If possible test the engine with a temporary coolant system connected. This will show if there are any problems with a head gasket leaking coolant. I personally would NEVER buy or even consider buying a Cummins B series engine that was demoed on Youtube or anywhere else showing a run time of over one minute without coolant. Of course, you may get lucky or your results could vary. That's your own personal choice.

EDIT: I can't believe I omitted this! BUY, BEG or BORROW a service manual BEFORE you begin any repair. There are a few unique procedures that in implementing are different from the things that you may have learned in repairing other engines. The service manual also shows tolerances of service acceptance on questionable components, ie; cylinder head cracks.

Do a compression check. This procedure can be found in the Tech Topics Index. Use the correct test gauge! These engines are far easier to work on whenever they are out of a vehicle.

Check your crankshaft end play. It should not exceed the approximate thickness of a matchbook cover. If in doubt, buy or borrow a dial indicator and make sure. There is a well know thrust bearing problem found in some of these engines. This procedure can be found in the Tech Topics Index.

On a running engine, if you find that you need to replace a head gasket, reseal the injection pump, replace the lift pump, install a governor spring, replace the injectors, I highly recommend the following to be incorporated. Incorporate only one component repair at a time and restart the engine. Then on to the next item to be replaced. It seems to be a very common recurring situation where a person unfamiliar with one of these engines does multiple repairs and ends up with an engine that will not start. This creates a situation of many variables and turns the usual long distance internet diagnosis into a nightmare kind of crap shoot. IE; replace the injectors and restart, reseal the pump and install the governor spring and restart; replace the head gasket and restart; etc. This narrows the problem down to only one repair and makes troubleshooting focus on only one problem area. Granted you may need to repeat removing the injector lines but that is a lot easier than trying to sort out multiple repairs that have multitude of possibilities.
 

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AMEN! That's some of the best advice you'll EVER get!

Many threads have come up on many forums where a guy decided to replace everything but the lug nuts, never having worked on a particular engine type before, and maybe with very limited mechanical knowledge & experience. A recipe for disaster there, plain & simple!
 

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Now that is some good advice for us beginners. I'll have to check and see if the engine I bought has been run without coolant and how long. Seller is a reputable guy and the engine is a recent Jasper rebuild. How worried would you be? How much should I check/fuss? I wasnt gonna make any changes to the motor until I got it in there and got it running. But is there something I should do while its out - like the killer pin? Nervous:D
 

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I installed my engine and then pulled timing cover while I had radiator support & fenders off. Dowel pin was ready to fall out, already backed partially out of hole! Made a simple keeper for it out of heavy sheet metal and fastened under the closest bolt. Thought what the heck, I'll check the rest of the timing housing bolts while I'm in here? Holy shitzky!

2 or 3 [right above gears] were hardly finger tight, 2 had about 5 lbs torque, a couple had maybe 15 lbs, maybe?!!! Just waiting to cause a whole world of bad news, somewhere out on a long deserted road when my checkbook was empty.

.
 

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rear main seal

really good advice! having recently done my 1st conversion, my one big regret so far is not replacing the rear main seal. i pressure washed the engine, ran it on a bare frame for quite some time (with cobbled coolant system), and didnt see obvious evidence of leaking.

obviously would be TONS easier to do engine-out.

bob how do you feel about doing this preemptively during a swap?

kevin
 

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Sticky?
 

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Really good point, Not just for Newbies !!

Ditto what is said above, and add double exclaimation points!!.. I have said this more than once on different posts where someone is going to do multiple MODS. They generally end up with multiple problems.

One thing at a time is the smart way to work on anything. And this advise is not just for Cummins engines alone.

Randy
 

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Agreed with all above. Newbies please educate yourself and read Bobs stickies, buildups on swaps, surf like mad, lots of good info in here. I know how easy it is to get excited about your build, but there is no instant gratification, lots of patience will help. Inform yourself.
And pre install for me was front and rear mains, kdp and 366 spring. Actually did a lot more than was needed(gasket kit) after getting into it, but still peace of mind. And only because others informed me of headaches and "watch out for this" forthcoming. 366 when its a foot into engine bay and up against a fenderwell looks to be a bitch. Piston fuel pump would also be alot easier with engine out.
 

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Yeah, as a newbie I know that with this stuff disaster and heartache are only a twist of the wrench away. There is a mental zone to be in when you are tinkering with complicated delicate parts that you don't know about. If your PO'd about something or hungover - not a good time to replace a governor spring or tear down your fuel pump. I sweat a little in anticipation of some of the stuff I'm planning for the first time. Better off asking dumb questions and looking stupid for a while. Kind of like the first time you touched that thing, you know what I mean. Just my $.02

Where's the best place to get all the gaskets - seals and stuff I need for my engine, 105 hp 4bt from 86 p30?:)
 

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Best teacher!!!

Man I've trying to figure out away to keep some of these guys from tearing into their rigs ...Fix only one item at a time ..
.KISS.....
.KEEP IT SIMPLE STUPID.....
I Can't do it all but I have so many resources ...I can get mine going ,But I sure worry about some that tackle some projects ..
 

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"Where's the best place to get all the gaskets - seals and stuff I need for my engine, 105 hp 4bt from 86 p30? "

Best to start a new thread in the General section. You'll have more people see it and also get direct answers to that thread topic.
 

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Judging from the number of "I did this and this, now it won't run" post this probably is good advice here.

But I don't understand what's so confusing, why can't folks fix a number of things and make it run again when done? Are these Cummins not simple engines?

I have very little knowledge of the Cummins engines, and some knowledge of the Detroit 53 series I play with.
When working on the Detroit it never occurred to me to do one thing at a time, just figured it all has to be done why not do it all at once, it's more convenient and quicker that way?

Today I'll have my engine stripped down to about the short block, only the head, valve cover, crank, rods, pistons, block, and front covers will be left together. Have already or will remove oil pan and pickup, front mount, cam and balance shaft pulleys, crank pulley, governor, fuel pump, blower, flywheel, flywheel housing/rear gear cover, gear train, end plate, water pump, oil cooler, filter adapter, manifold and turbo.
The plan is to get it ready for paint, and to switch or change most of the parts I removed for different ones and or bolt them back on in a different place.

Perhaps I'm naive or optimistic, but I fully expect it to run within about 10 seconds of cranking once all back together.

What makes a Cummins more difficult or confusing?

Grigg
 

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The difference is talent and experience. SOme people ain't got either. That's why I go slow and check everything three times.:)

Find when your putting something together that you are not familair with the stress level is high and have to be alert to if it functions properly and am I braking the d**m thing!

CrewCab59 was kind enough to point this stuf out to me and I thought it might be good here. Hope he doesn't mind. Told him didn't want to mess with engine too much and what do I have to do with engine out.
--------------------------------------------------------------------------------

"1. Gov spring can be installed now or later.
2. Can advance your timing a bit if you like.
3. Do the KDP tab repair,you also need a front seal and a gasket .
4. repalce the rear seal before you install the engine.

Some things to check

1. Crank end play ( thrust bearing ),
2. Vlave cover gaskets ( gray ones are updated ),cover bolt O -rings.
3. The head gaskets were updated to gray ,the black ones leaked at the right front ( stat ) .They also leaked 3-4 cylinder .
4. Think about where your going to place you oil sender ,heater in and out, and coolant sender."

and

"# 4
OIL
You have 2 oil ports on the left side of the engine near the denter line of the engine block in the web. COOLANT
You have a plug in the left rear of the head ,that the hotest place for the sender.

All you need is brass bungs adapter to fit the stock senders or the new gauges depending what your using.

Heater Hoses.

run in the lower water neck and top at the lift eye by the stat."

Hope that is good info
 

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Grigg: yes, they are relatively simple engines however, as you have no doubt witnessed, people can and do get into trouble, and can't find their way back out when they blindly start twisting on stuff. How many times have we seen guys who have a running engine, that is not running right, and they want to install bigger injectors and tweek the pump to get it to run better, instead if fixing the real problem it has got, which is usually something like changing the fuel filter..

I have a pretty good understanding of these engines. I have taken one completely apart, looked at all the piece parts, noted the differences between these and other engines I have been into, and I think I could put it back together and have a reasonable chance of getting it running. Mainly because I have a engine manual which has step by step directions, and I can follow directions. I'm considered to be mechanically inclined by most.

If everybody just followed the instructions, they probably wouldn't have nearly the problems they have. Most people dive in thinking they know what they are doing, only to fail and then consult the instructions. Not just engines here, this also applies to assembling Patio Furniture.:idea:

When it is already together and you can't isolate the problem of why it won't run or will just barely run. Then tearing the engine down and rebuilding it is probably not the answer. The step by step approach to trouble shooting is the logical way of doing things, and I'm sure this is what you would do too.

When a guy has an engine that runs and then he starts "tweeking on it" to "enhance performance", and it gets worse or ceases to run at all, then he really needs to be able to retrace his foot steps, and figure out where he went wrong. The "tweek run, tweek run" method is the best solution to avoid this situation. The less steps you have into uncertainty, the more likely you are to find the problem before you bury it underneath a bunch of other problems.

Where I see this the most is guys fiddling with the IP. I have the Bosch Book on VE pumps. I have read it through 8-10 times (it was toilet reading for nearly 2 weeks). There is no reference in that book on "enhancing performance" or how tweeking adjustments affects the engines running, no reference to tweeking timing. It is all about specific settings, achieved on a flow bench, and it doesn't talk about those specific settings, as they are contained in the CPL book that all diesel pump repair shops have, and we probably don't.

I pretty much understand how it works. I would not attempt tweeking on it simply because everything you do off of flow bench is "tweeking in the blind" and will probably result in less than optimum operation in some part of the power band. That's not to say an "Experienced Diesel Mechanic" can't tweek stuff and improve the way it runs to some degree, but the average BOZO is probably better off not.

The reason for this is simple. THEY DON"T KNOW WHAT THEY'RE DOING!:rasta:

I hear things like turned the "star wheel x number of turns", and 1 turn on the fuel screw. There is no reference to a star wheel in the Bosch book anywhere. I don't even know what it is, or if a VE pump even has something that is locally called a star wheel.? IE: I am not qualified to tweek a pump.

I do know that cummins engines are available in about 50 different power ranges, and for the standard Dorito Van engine there are probably 25 settings from about 90 hp to 130hp. These different HP/ torque setups are designed to deliver "predictable" performance for specific applications. Pretty much the only difference between the setups is the way the pump is set up on the flow bench, along with the injectors, and the way it is timed when reinstalled. These are about the only variables, but they have relationships to each other. IE they are calibrated to work toghther

Specific adjustments of the pump and injectors, yield specific results in power. And whereas minor tuning can be achieved and enhance "calibrated performance", it needs to be done by someone who understands exactly what the effects of what he is doing, are. And IF you know what you are doing then you are probably going to do one thing at a time anyway, because that's how people that know what they are doing, work on stuff.

As far as Detroits are concerned I think they are even more "cut and dried" than Cummins motors. Aren't there just 1 or 2 HP ratings for each of the 53 series 2 strokes? If the injectors are set up per spec, (run the racks) the engine runs if it has got fuel, and that 's about all there is to it? The Cummins motors just have more things to tweek on than the Detroits do, and this is where the problems start.

I personally think that it all comes down to knowing your limitations, and working within those limitations. I just took my new radiator to a radiator shop yesterday to get it modified.. I know how to solder a radiator, but I don't have a hot tank or the stuff a radiator shop has to do the job right. I know my limitations here and I took it to someone who is better at it than me. I think this concept applies to just about eveything, with the possible exception of dire emergencys, where you do what you've gotta do. Then you need to read my signature again and understand what it is about. :nuke:

Randy
 

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Discussion Starter #15
Thanks for the reminder. Post #1 edited to include getting a service manual.
 

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If everybody just followed the instructions, they probably wouldn't have nearly the problems they have. Most people dive in thinking they know what they are doing, only to fail and then consult the instructions. Not just engines here, this also applies to assembling Patio Furniture.:idea:
Even more critical is the ability to spot, before you've made an irreversible move, when the instructions are wrong. (Or maybe that your interpretation of them is faulty.)

Case in point: I recently changed out the blower motor on my truck. I've got a Haynes guide for it, and I read through the steps and looked at the pretty pictures the night before. I also mentally went through the motions of doing the job the next morning before attacking the thing.

Well, wouldn't you know it, when I hit the part about sliding the computer to the rear to pull it off it's mounts.. Nope. Double check book, no "exceptions" or "most models", just a "pull to rear to remove from mount". Yeah, right..

So, I looked at it more, and the motion was to the side, not front/rear. Now, true, not a big thing in itself, but when you're applying force to ~20 year old plastic parts behind the dash, you can bust stuff that may be a bit hard to find in a hurry. (And yes, the realization "Well, this WON'T be here after I shove the Cummins under the hood" did cross my mind..)


Oh, and assembling patio furniture, with the "loss in translation" (not to mention the "loss in transportation") that is so typical these days, is probably WORSE than a full rebuild of a 4BT... ;)
 

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A good manual is a huge help, I too read the pertinent sections the night before working on new, unfamiliar, or forgotten parts.
Also a good idea to have a clean copy for the house/bedside and a copy for the shop.

Another tip, copy the page of torque specs for your engine and hang it on the wall in the shop, then refer to it when necessary.

Are the Cummins manuals good? I know the Detroit manuals are excellent, and the manuals for the Komatsu forklift I use are just about worthless..

Grigg
 

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The Cummins manuals are as good as I've seen. They have step by step proceedures for complete tear down, and assembly of the engine itself, along with warnings of prattfalls, and torque specs for everything. Good pictures.

I have The B Series Shop Manual, The B Series Operation, and Maintenance Manual (5x8 size), the 4B series parts catalog, the 4BT/P30 Parts Catalog and the B series Industrial Sales Manual which shows all of the optional equipment available for land based engines. Never could find a Marine version of that manual.

The Bosch VE pump manual is a little more complicated. There are explanations of all of the rotary pumps in the same manual and instead of covering one pump completely, and then moving on to the next one, they discuss a specific function of all of the different pumps, and then move on to the next function. This means you have to be thumbing thru the book looking for what you need to know instead of just going to a particular section about your device.

It took me the better part of 3 days to figure out how a VE pump works. Reading, re-reading, then looking at my engine, then rereading again.
The device is really NOT that complicated, however the manual is not layed out the way I would have done it. It's made by Germans, what can I say.

As I said in the above post, there are NO references in that manual to "tweeking the pump". There are NO references to what the effects of each of the adjustments have on the operation of the engine. These fuel injection pumps are supposed to be calibrated to specific specifications on a flow bench along with the injectors, and then installed on the engine, with the pump "pre-timed" and lined up with a specific timing mark, and after this is done you should get X performance. Period! Very simple! Right? This is true if it is on a Cummins engine, or a VW engine, or any other engine they use the VE pump on from completely mechanical, thru mechanical over electric, to fully electronically controlled. they all are initially set up the same.

I think they did this to Idiot Proof them?

I want to say in closing, none of this was written to discourage or belittle someone who wants to play with their engine and try to wring more performance from it. Many here have been very successful tweeking their motors for better performance. All I'm saying is that you need to do your homework, and that means from a variety of sources not just 4BTSwaps. And you need to use an "Empirical Approach" IE: take a step, note the changes, move ahead, and so on. You have a greater chance of success if you follow this approach. Blindly twisting on stuff , cuz someone said so, is NOT the way to go.

Randy
 

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Factory settings are for longevity.

Edit: Please note that injector pumps can be dangerous. They should be bled off properly before servicing. They can blow diesel fuel under you skin and cause an emergency room situation. In the words of the immortal genius, Curly Joe: "NNNNNyaH!"
 
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