Thook, thook without air cleaner. None audible with

[Dirtleg]

Well I am hoping it's a minor issue rather than a major one but here's the description of what's going on.

Today I put in the fuel line olive seals between the filter head and pump. After bleeding the injectors and getting it started I am hearing a pronounced Thook noise. I one at a time loosened each injector and it made no difference other than a shake as each injector was cracked open. The sound didn't change. Well wanting to make like an Ostrich and just put my head in the sand about it I stuck the air cleaner back on and the sound went away. It's not coming through the exhaust at all so I am thinking intake valve. What are the potential causes and best/worst case scenarios here. I am currently in no position to be buying any more truck parts but cannot risk dropping a valve or destroying the engine with the 1500+ mile road trip I have coming up.

Thought and suggestions appreciated. Valve covers will be off today BTW.

 

[yARIC008]

Probably just a valve not seating 100%. Mine does basically the same thing and it's been that way for 50,000 miles or so. With the valve covers off look for any excess movement in any of the valve keepers/rockers all that good stuff. Make sure you don't have any fatigue indications on any of the rocker arms. If everything looks okay and is well lubricated you'll probably be fine. Changing the valve stem seals may help some but that isn't exactly to do with the head on the engine. I guess it's not impossible but you have to be careful to make sure you don't drop any valves in.

 

[towcat]

I went through the same thing with mime. Only difference it was doing it through the turbo and you could hear a mechanical noise when it was warming up in the morning. your comfort level will dictate if it's driveable or not. There's a reason for the soup bowl and it's job is to muffle those noises since there will be some. When it gets real bad like mime, there's no mistake. My truck was running pretty rough until it warmed up. I drove back from TX to Kali with the noise. I won't do that again.

 

[Dirtleg]

Well the truck runs really well overall. I just took off the drivers side valve cover and everything in there is seemingly perfect aside from a little sludge (240K miles). None of the rockers are loose at all. Pushrods are seated properly and straight as near as any visual inspection will tell you.

Is there anything else that I should look at while under there?

I've been hearing what seems to me like a slight lifter ticking for some time now. Everyone else who's listened for it says they don't hear anything outside of normal diesel sounds. So I figured it was just paranoia on my part.

Well off I go to remove the PITA passenger side valve cover.

 

[subway]

wouldent a compression test show something up real quick.......use the $18 cheepy from *cough* harbor freight *cough*

 

[Dirtleg]

That is good advice but I dare not disturb the glowplugs until I am back in Virginia unneccessarily. I have not been having good luck in this area lately and I am not willing to risk the possiblility of losing a tip in a cylinder.

Truck does not smoke, has decent power and starts easily. Only when I let it sit too long do I have any issues and that's air coming in from the fuel filter heater o-ring.

While on that subject it appears the filter will have to come off to remove the passenger valve cover. Since I have a leak in the filter head heater and the o-ring to fix it what tools will I need to change it out. I do not want to remove it twice and it's already on the list of things to do but I do not want to start it only to find out halfway through that I cannot finish it. I am 24 miles from the apartment and have to drive there so once I am started it's a total commitment. I also keep a new filter in the truck so at least that's a non issue.

If I didn't have total automation communication failure today I wouldn't even have had time to mess with this. Seems like one can of worms leads to another.

 

[suv7734]

While the valve covers are off try to push each intake valve (may as well do the exhausts as well) sideways at the top (retainer). You are looking for valve guide wear.

 

[Dirtleg]

I did that on the drivers side but everything in there was tight. That's not to say a valve wouldn't move but none of the rockers had any play whatsoever and the valves were all in contact with them hence no movement.

I scrapped the idea of taking off the passenger side valve cover today because there are too many issues that need to be dealt with during that operation that I cannot afford to fail on even one of them so it will have to wait until I am certain I can get them all finished. Hopefully there isn't a major issue and I can drive it until then without incident. Don't have a choice unfortunately.

 

[suv7734]

Sorry, forgot to mention you need to remove, or at least loosen, the rocker arms. You might also want to crank it over (FSS disconnected) with the valve cover off to make sure all the valves are opening the same amount (looking for camshaft/lifter issue) if you haven't already.

 

[Dirtleg]

Well it appears I will have to wait until I have a day offdunno ) to fully diagnose things. Maybe this weekend but I don't know just yet.

Thanks for all the advice so far. I am not usually flustered so easily but this past 6 months I've been way too busy and stressed. So much so that I am wearing out. I need a vacation. (who doesn't)

Also is there someplace besides the dealer where I can get a single, dead ended return line cap for the #7 injector. Figure if I'm going to open up the fuel system again I ought to get that ready for the turbo. I cannot get to a dealer during business hours.

 

[Diesel JD]

I'd let the injector orings and caps ride until after the turbo install is done unless its leaking real bad and just HAVE to fix it NOW

 

[suv7734]

The idea of doing the o-rings and caps at this point is the return line that runs from one side to the other is at the back of the engine on a N/A setup. With the turbo it is moved towards the front with a tee usually in betweeen #3 and #5. This keeps the return line away from the turbo and potential heat.

 

[Diesel JD]

Oops! I didn't do that with my ATS install... so far I don't think I've melted it.

 

[Dirtleg]

Yeah I don't have any intention of doing all the o-rings and caps at this point. I just want to replace the one on injector 7 with a dead ended cap. Anyone have an idea if say NAPA would have this part by itself. The parts guys at the NAPA here have an unusually hard time of finding parts. It's one of the truck centers and they have a huge parts warehouse but they are not good at finding things. If I want an unusual part I have to bring them their part number or it's a no go. But at least it's close by and I can get there during business hours. And they usually have what I want I just have to bring in the part number.

 

[Dirtleg]

Update, this morning I took the valve covers and fuel filter assembly off the engine. I replaced the fuel heater o-ring. That was super easy.

For anyone who wants to know a 1/2" drive standard depth 1 1/4" socket will work just fine. In fact due to the fact that it's not recessed in any way you could just put a 1 1/4" box end wrench on as well. I should have taken pictures and probably will before I reassemble it. I searched for this info but it's not always easy to find as it seems the placement of info can be so random.

I then loosened all the rocker arms and tried pushing each valve to the the side. Not a one of them was noticably looser than any other. That is to say if I pushed really ******* them there was a minute amount of flex in the spring to the side but the valve stem doesn't appear to move.

So I guess that's that. Now I have a mystery noise? I will get a video of it running once it's back together so that ya'll can tell me if I'm crazy or something. Don't get me wrong I'm happy I didn't find a loose valve. Just a little confused. I neded to change out the passenger side VC gasket anyway.

Now I figure I'll just relocate the GP controller while I'm in there. Won't hurt to do it now I suppose.