knock out of the intake

[pirate]

I'm new here and with diesels. I have a 97 gmc k2500 4x4 with the 6.5 turbo diesel. I was on the hiway going out to the mountains, going up a hill, looked at the gages was fine then lost power and overheated while passing someone. It appered that the head gastket went. Got it towed home and got it running, ran like a bag, lots of smoke.( white and smelled like diesel) changed the head gasket, still runs horrible. the glow plugs wont turn on but you hear the relay click. not sure if i have power down to the plugs. when you get it running it smokes till it get warm, looks like myt house is on fire with all that smoke. there is a knock out of the intake, if you stick your hand over the intake the knock almost goes away at least i could probly ingore it but it sounds terrible. When the heads were off i looked really close at the heads they looked fine not warped or cracked. i borrowed a obd2 code reader and all i could get out if it were the signels from the gages, so not sure if i needed a different readed or not?now the question i,m having is how do i tell if the engine computer is dameged, and needs replacing? if not where else do i look i would like to get this truck running. when the truck is running i get lots of smoke, it idles at 1000 to 1100 rpm, the motor shakes, and you hear a knock out of the intake. the knock is not a metalic sound its just a thump. please help if i cant get it going its gonna go to the dealer if they will touch it but i would rathere fix it my self
thanks

[pirate]

well i got truck to dealer and they were being stupid. they wanted to sell me a long block for 10000 thanks but no. So now i,m looking for where to begine with troubleshooting? the glow plugs dont turn they stay cold but the realy click, needs new plug? is it worth the cash for a compression tester? how do i tell if the. lift pump is working? what about injectors if removed can i tell if they are bad? any help is appreciate

[Robyn]

The overheating wa most likely due to a blown hed gasket if you now get lots of smoke.

The thumping noise from the intake is most likely caused by a collapsed lifter which messes up the valve timing or something stuck under an intake valve

The compression tester is a valuable tool for checking the condition of the engine.

If the glow plugs dont work, how have you been starting the engine?

With the issues at hand the only real plan is to get the engine out of the truck and apart.

A blown head gasket is not the end of the world on one of these and can usually be repaired easily.



As long as the thing is not thrashed it can be fixed well for a modest amount of $$$

$10K for a long block is rediculous.

Keep us posted and we will help you get your beast nursed back to health.

OH BTW when you rip it apart be sure and mark the IP to the case carefully and this will allow you to get things back together and going without the need for a tech tool to time it with. :)

Reread your posts again..... When you replaced the high pressure lines to the injectors you may have crossed two lines. This will make them run terrible and smoke horribly.

Check the routing on the lines and be sure they all go where they need to on the IP.

Best

Robyn

[john8662]

It appered that the head gastket went. Got it towed home and got it running, ran like a bag, lots of smoke.( white and smelled like diesel) changed the head gasket, still runs horrible.

When you replaced the gasket and installed new bolts (required) did the gasket really fail?

They're really prone to failure on the ends near the odd-shaped coolant port.

I think everyone is on track so far as to the troubleshooting, gotta have the compression tester though, saves tons of work and helps identify where you need to pay close attention to.

Possibilities:

*Rocker arm retainer broken.
*Pushrod not in place after head gasket replacement.
*Bent Pushrod
*Lifter malfuntion, collapsed (not really that common, but seen it)
*Injection lines on back of pump not in right order (a couple can be reversed).

[pirate]

well i finally got it up and running today. changed the glow plugs and the relay. yaaaaaa it runs it makes lots of smoke that smels like diesel and it almost goes away when idling step on the gas and more smoke. temperature was comming up off the cold line and it just died started it again and it ran for a few more minutes and died ,the knock is still there thou. i,m gonna pull the valve cover off and see if a pushrod is bent as long as its not snowing. after it started it ran very nice no unusual shaking or hi idle like last time. i guess ithe question now is since i overheated it on the hiway and it just died there as well is there something else that i need to look at or change? the pmd? idont have parts so ihave to buy them as ineed them so im slow thanks

[pirate]

sorry missed you answer yes it was damaged at the front of the pax side num 2 maybe but i might have done myselff taking the head off. any ideas if it is not a gasket, same symptoms but no head leak? im open to ideas

[simon]

in addition to above suggestions.
Pull the injectors and have them tested,you could have introduced dirt in them while R&R'g the head[s]and one or more is stuck wide open.
You could also have a piece of material stuck between or a bend intake valve,keeping it open far enough to hit the piston on up stroke

[pirate]

so i pulled the valve cover and evey thing looked good. tried starting it and it ran but it sounded like it was not getting enough fuel for a bit then just picked up and ran fine except for the smoke lots of it still. ran till it started to get warm then it died started right up and ran fine for a few more minutes then died started it again then turned it off with the key. the knock seems to be temperature realated since it was almost gone. i have 4 more glow plugs to change. are these symptoms of the pmd failling ? or fail ? i now have a hard failure as i have the check eng light on whitch i did not have befor not sure what it is as the reader does not read the truck .btw the truck is a97 34t 4x4 if it maks a diffrence . thank