no power long story

[lastbugle]

Hello
My name is bill I just found out about this site a few days ago and am glad I did I already read some good information. You folks really seem to want to help!
I have a 1992 Ford 7.3 diesel ,automatic rebuilt four years ago . I bought it in 2005 it has
175 thousand miles. It has white smoke when it starts, white smoke pulling hills not real bad. When I bought the truck the person told me it got 20 mpg so I figured 17 maybe 18 thats what I had heard they got, I have never seen better than 13 empty or loaded. I have a problem and from what I'm reading here I think maybe I have a chance to get some ideas from you fine people what to try or do.
Here goes the story.
I was hunting last fall I have a 8 ft camper and pull two horses, I was going up a hill when I suddenly saw steam coming out from under the hood which totally caught me off guard because this truck never got hot, the radiator blew a seem. I was almost to the top of the hill two lane road with no pull out and curves I felt I couldn't stop right there so I pushed it until a safe place. but as I was seeing my place to pull over the truck was dying from over heating floored going 15 mph and fading it got hot!!! I let it cool I had water to refill. nearest town was 60 miles back. I had lots of water so I headed back (over 8 hours to go 60 miles long day) it overheated a couple of more times but nothing like the first time. I made it to wall mart got some solder fixed the radiator drove home 200 miles no problems took it real easy.
after I got home I noticed the water pump went out I fixed it.(no oil in water, no water in the oil) seemed to run fine although there was a new sound at idle a hum or vibration that seemed to come out of the air cleaner I put my hand over the air cleaner and the sound is muffled any way like I said it seems to run OK and even though it lacked in power now it can't hardly get out of its own way example going down the freeway flat road truck only its almost floored to go 60 or 65 mph. definite power loss. my funds are limited so I need to do as much as I can myself, I have mechanical back ground but not in diesels.
Heres the question whats the best guess that I probably hurt, anything I can do to test or try? Where do I go from here.
Thank you in advance for any and all help!!! lastbugle Bill

 

[jperecko]

Are you losing coolant? It sounds like maybe your head gasket went. They tend to do that when you overheat these engines. It can fail without leaking coolant into oil or oil into coolant. It could just be letting coolant into the cylinder. Another option would be cavitation. Or it could all just be a tired fuel system that a new set of injectors and pump would fix. I am sure some others will help you get it focused a little more than my vague diagnosis.

 

[Agnem]

Overheating really kills these things in a hurry. Blown gaskets... cracked heads, anything is possible. I'd start with the basics and do a compression test, and also presurize the cooling system with the glow plugs and oil pan drain plug removed. Keep 13 pounds of presure in the rad for a day or so, and turn the engine over by hand. If you don't have coolant coming out anywhere, then your good there, and hopefully your problem is just that you need new injectors and a new IP.

 

[subway]

yea you want to start a diagnosis, you can rent cooling system pressure testors from any big box parts store. if the system holds pressure for a while it is sealed, if not, like Mel mentioned you need to find out where it is going.

a compression test is great to but the testors are expensive for diesels.

is it possible the injection pump could be loose or have been moved at all in your working on it, changing the timing can really knock the power out of these trucks.

 

[lastbugle]

yea you want to start a diagnosis, you can rent cooling system pressure testors from any big box parts store. if the system holds pressure for a while it is sealed, if not, like Mel mentioned you need to find out where it is going.

a compression test is great to but the testors are expensive for diesels.

is it possible the injection pump could be loose or have been moved at all in your working on it, changing the timing can really knock the power out of these trucks.

Is it possible for me to check this timing or do I need special tools.
and as for the compression tester if I can do it I would rather buy it and have it for the same price they charge to test it unless its more than a couple hundred bucks. the shop I called charges $104.00 an hour. wasn't ready for that. Thanks

 

[jperecko]

I go tmy compression tester from Harbor Freight for around $40 I think. They also have a coolant pressurization kit but I have not tried that one yet. It is cheap chinese stuff but it works just fine for me.

Timing takes some special tools that are around $150-100... but I do not have those yet either. It can be done by ear though.

 

[subway]

i have the harbor freight compression tester also, i think i paid 20 for it on sale. it gave me a reading but it broke the second time i used it not holding my compression pressure. i can still use it if i watch it, they also dont have the right adapter but you can use another in there kit.

a good one is a couple hundred, timing is also set with a special tool that reads the flame in the cylinder (optical) or the pulse of the injector when it fires. again special equipment is needed to check that right. you need a 150 dollar adapter to hook up to a timing light or meter. if you can find someone near you with one it is much better. timing can be set by ear but it is very hard to get in spec even by an experienced person.

edit: found the adapter
http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=FERV765-01

not tying to be discouraging with pricing, thats one of the reasons i was thinking of first checking the cooling system because you can return the gage and get your money back when you are done.

 

[lastbugle]

so OK I get a compression tester I was told to take out the glow plugs to test in that hole is that right and are they little skinny things next to but below the injectors and how do the tops come off their plastic and look brittle, then do I need to do anything special or unhook anything how do I keep it from starting, do I take out all the plugs or one at a time Ive just never done it on a diesel. thanks for you're Patience & help.

the cooling I actually have a pressure tester I forgot I had it.
I put it on and found a hole still in the radiator at the top so I'm still not sure of cylinder leakage. $300.00 radiator in my future.

Also I think I understand cavatation but why does that cause power loss. other than wearing through the walls I could see that.

 

[subway]

yup the skinny things, you pull the all glow plugs out, the brittle part i think you are talking about the connector at the top. they get like that from the heat. you can pull the wires off the injection pump so it wont shoot fuel at you while you crank it over.

cavitation will cause the same power loss as a blown headgasket basically.

you might be able to just fix the radiator yourself with some solder and a propane torch, i have done this multiple times. as long as the whole radiator is not worn and paper thin it should be fine.

 

[RLDSL]

You also need to get a combustion gas leak detector kit , About $50 from Napa, a little more for a better two chamber job from Snap on.
It is a coloured dye you hold in a chamber over the water neck while the engine is running, and if the head gasket is blown or there is cavitation broken through the water jacket and there is combustion gas present in the cooling system, the blue dye will change colour to a yellow green. The two chamber one is best because it prevents contamination in the second chamber from direct contact with coolant.

 

[david85]

All you really need to do for a possible leaky head gasket is to make note of what the recovery tank is doing and if the rad hose stays hard even after the engine cools back down.

Its normal to see the hose get hard as the engine warms up and reaches operating temperature, but if its still hard after cool down, then something is wrong. This test only works if your rad is well sealed though. Foaming coolant getting pushed out the overflow line into the expansion tank is also a dead give away.

I wonder if the lack of power could be from the injector pump overheating. From my experience, a mildly leaking head gasket rarely causes a major loss in power.

 

[subway]

another way to test for cavitation or head gasket is to put the coolant pressure tester on the engine when it is cold and fire it up. the pressure should rise slowly on a healthy engine. a head gasket or cavitation can pressurize the system very quickly.

 

[lastbugle]

Hi
I just wanted to say thanks for all the help!
It will take me a little while to try all the ideas but when I do I will let you know the results.

p.s. last question the plastic caps on the glow plugs do they pull off or pry off or is there some kind of clip release I don't want to break the caps and I'm afraid I will because their so brittle???? then when I get them off I take it (they glow plugs) screw out regular not backward or anything.
thanks again.

 

[Michael Fowler]

lastbugle,

WELCOME to the site. You have already "met" some of the knowledgeable people here. Trust them.

Since you are new, I would suggest ready the "sticky" at the top of the page on IDI tech artciles. There is more information there than many so-called diesel expert mechanics will ever master.

Again, Welcome.

 

[subway]

the connections at the glow pug connections just pull off, they should be the "bullet" style connector. side note, if you loose any of the connectors i have a yellow size wire crimp on one of my wires a previous owner put on and it works.

and yes the glow plugs "should" just screw out normally. something to mention is that if the glow plug is having problems coming out or breaks the tip can fall into the cylinder which is bad news. to prevent this you can put the piston at TDC on the cylinder you are pulling from so if that ever happens you can vacume out the tip through the injector hole. i have never had a problem but it is something to be aware of.