Out of Nowhere Comes A Knock (1 Viewer)

[cruiserine]

Fellas, all alone here with a 3b with a knock.
earlier today i started her-up, as she ran as usual i added around 5 gallons of bio diesel (around 10 min.)
shut her off for 30 min. then out of the blue i'm getting this knock.
oil topped off ...
the night before i moved the sediment container from where it was attatched to,
to the fire wall.
i opened the top 10mm to see if i might have gotten some air. there was
some room for fuel so i topped that off.
thinking that i got air in the line i've been truying to bleed air post the sediment container.
well still knocking.
i didn't get to the back two injector to bleed, thinking of 't' ing off the fuel return.
but i'm not sure if air in the line is the cause of the knocking.
kinda scary and nerving.
she does smoke white some and should be still warm from warm up.(no smoke
when warm)
i noticed i had vacuum built-up when i opened the cap, but didn't run any different as i added the fuel in the tank.

question can i bleed air from the injectors like i would the brakes?
pump the fuel hand pump, hold it down and open the injector,
close then release the pump.
i feel like i'm wishing its just air in the line, ...

appreciate any input on diagnosing my situation if it would bee a
spun bearing or dropped pre-cup

thanks,
n8

 

[roscoFJ73]

question can i bleed air from the injectors like i would the brakes?
pump the fuel hand pump, hold it down and open the injector,
close then release the pump.
...


thanks,
n8

This is how you are supposed to do it,but if you have it running ,the engine should self bleed after 5 mins or so.
Maybe the inline pumps are not so good at this.

It could also be bad fuel.Ive heard of others getting a knock after adding a new lot of bio fuel.

If it was mechanical it would have most likely have come on slowly.

 

[cruiserine]

thanks, i'll give it a shot tomorrow.
i might have broken the steel fuel line that connected to the sediment container.
it is pretty crunchy and i had to bend it some.

hopefully i'll have some good new tomorrow.

cheers

 

[roscoFJ73]

thanks, i'll give it a shot tomorrow.
i might have broken the steel fuel line that connected to the sediment container.
it is pretty crunchy and i had to bend it some.

cheers

I will think you have found the problem.If so you won't get the air out.They can be braized or soldered by someone competant

 

[cruiserine]

well i struggled to bleed the air out. got good pressure with the prime pump.
rinsed the water seperator, and added a secondary filter.
ones i see on mercedez and vw.
one trick i found to bleed the air out of the water seperator is to hang it
as low as possible and pump the prime pump.
the clear secondary filter helps with visual situation of fuel mvement.

Okay. but still got the knock and now it seems as i am loosing oil.
somewhere below the oil cooler housing, though i'm not sure.
got a rachet on the front to turn her over by hand, feel it compress one cylinder then stops.
i don't hear any 'clunk' or anything, just lands on something.
turn it the other way, same amount and again, stop

strange that this just appeared.

so now i'm thinking, ....
check the valves ....
drop the pan in check the crank.

if i can't find anything then i would think that i will pull the head.

open to any ideas.
take care,

......

 

[cruiserine]

oil level looked good. might be all the fuel i spilled.
got all g.p. s off . the last one on the back looked to have some flakey deposits.
i'm able to turn over by hand about a full turn, till i gets jammed. hear compression through first and second cylinder though.
i haven't put much force but feel like a good jam. i think if it was running with the same resistence something must have gave.
always started right up, but don't think i'll do it again till i know where its coming from. daaaaanng.
i'll see if i could get my friend to turn the motor as i get closer to the engine compartment. from directly in front sounds like its knocking from the exhaust side towards the back. he says he got a optical probe and a stethascope.

started to loosen the injectors lines to get to the injectors so i might be able to take a look. feel the lines kinda stuck to the compression fitting(?)
any tips on getting them off?
i don't think i'm ready to pull the head off, felt i just got over the first hump in this project and wanted to feel things out some.
but will try to drop the pan tomorrow if weather permits.

aaaiii

 

[cruiserine]

i' m here loosing sleep now. 7 am.
had athought. the last time i had her running good was when i was
filling here up with fuel at home.
i backed up to my barrel of bioD on the slope of my driveway.
i'm thinking maybe (having the nose of the car up) that caused a vacuum and sucked a valve .

well, gonna try to think things over to where to start.

 

[Wagnerwerks]

As a fellow biodieseler, are you sure you have no water in your current fuel? My Benz did a knocking spell when I had wet fuel one time. Also, clogging filters or a plugged injector can give you a heck of an injector knock. Just some thoughts. Good luck!

 

[cruiserine]

yeah, once i ran wet bio in my corolla w/1c. that was around 6 years ago and was running 100% b
on my cruiser which i only have put about 500 miles with a blend maybe 20-30%.
it is possible to be the cause though.

if one of the injectors are clogged and one or more of the cylinders aren't getting fuel,
what do you think would be damaged?

i ran it with this knock for maybe 3 min. trying to bleed the air out.


i drained the oil which didn't show any signs of metal but haven't dropped the pan yet.

still half motivated to start taking apart what i've been putting together for the last two months.

will see if i can get through to my 'psychic mechanic' .

any others out there that may tune in?

thanks for the support,

 

[roscoFJ73]

Take the glowplugs out and spin it on the starter. If its a mechanical problem you maybe able to hear it better.If its a air/fuel problem it should disappear.
It will spin quite fast without the glow plugs ,like a slow idle.

Or connect up a temporary fuel supply with fresh diesel from another source and see if the noise goes away.

There is a bit you can do before you bust out the tools and start pulling things apart.

 

[cruiserine]

thanks for the input. i'm gonna borrow my friend's scope to have a look from the glow plug hole.
i really can't understand how this could be and like you said don't really want to take all that i just put on off again.
but the resistance i get while turning her over by hand says there is something more than air and fuel (i think).
was thinking of a head gasket replacement anyway, since i had a little leak of oil.

thanks again for all the input, will keep thngs updated as i go.

ランクル　パワー
(lankulu(landcruiser) power)
in japanese

N8

 

[cruiserine]

okay this is my third try. token expired? ....
shot of the bottom end.
some bites taken off a couple cam lobes.
hhhhmmmm do i need a new one/
can i get a new one?

i like them squirters.

let me see if this is a charm

thanks

 

[hj 60]

The cams are not new and you can check: if you can feel any small damage with your nail then you have damaged cams.

But that cant make a knock, but the biofuel can stick the injector, maybe you can release it by heating the injector(s) with a blow torch, dont fry them but get them good hot and see if that melts the residu on them.
Or use some mix of diesel/petrol or any stuf that burns hot and not like veggie oil that combust too late compared to normal diesel. (timing)
next step is pulling them out and clean/test.

 

[cruiserine]

yeah, i think thats the original cam. wondering how those nix got there.
so i'm in search for a new cam or a new old cam.
can anybody direct me to a source. i meant to make some calls today.

drained the coolant and got the injectors off today. busted the return lines from the injectors.
(pissed me off) they were on pretty tight. slipped off my platform on the second i.p. and twisted off
the line.
all injectors had similar build-up. was able to take a peek (though the last one was tough), looks like them pre cups are still there.
wondering if the injector pump failed from contaminated fuel.
anyway to check the i.p.?
the timing gear cover is stillon maybe that will reveal some answers off.
so far things look good except the cam. was going to take another look from underneath but didn't feel
like crawling in mix of anti freeze and fuel.
sorry that this has been a guessing thread, hope to have some answers in a few days.

take care, N8

 

[cruiserine]

okay, .
got the head off. second cylinder was munching on something.
all the pre-combs are intact. looks as though the intake valve sits further in
compared to the others, but i don't know what them chunks are.
even wondering if i sucked something in through the intake.
cylinder walls don't looktoo bad, but found cracks in between the valves
in each cylinder of the head.

here are some pics.

 

[hj 60]

That looks really bad, dont know what you have to do to get this sorted, what went in there? These parts are massive...

It looks like cracked head = precup / valve seat pieces: https://forum.ih8mud.com/diesel-tech-24-volts-systems/592662-3b-precups-final-day.html

If these bits made it to the other side and are now in your oil and squeezed in between the cams and damaging them your engine will cost a lot to repair, maybe add another type engine?
Can you check the oil for particles? Your definition of knock might be better described as an insane smashing and grinding rattling sound?

new head, new cam, new cilinder hone #2?, new glow #2, new injector #2, new valves #2, new head gasket, clean flush engine oil, find smashed part,
Maybe the easy way is to clean it up and put it back together and see what happens?

How does the other side of #2 look: (2H)

 

[baxter650]

If you have a valve that is quite recessed it is most likely you pounded out that valves seat.
You might be able to have it replaced but more than likely you will be looking for a used head.
It may be cheaper to replace than fix.
As for the cam, it looks to me that the "nicks" are from a porous casting and have been there for some time.
If you are fixing the rest of this motor and the bottoms of the lifters are ok i would leave it be.
Pull the piston from that cyl and make sure the top ring land is not deformed, clean up the top as best you can and put it back in.
All this really depends on what was in the pan though, if it is full of fine crud, call it a day and find a replacement engine.
This is what i would do but others may not agree with my cheap ass approach.

 

[cruiserine]

popped the valves off and as i thought the seat
dropped.
so i will try to scrape and clean the piston and cylinder, see where i stand there.
don't think the head is worth putting back on even if i get a new seat in with them cracks.

so i am on a quest for a new head, or another 3B

open to any suggestion or leads.

thanks all.

 

[cruiserine]

Baxter, looks like you beat me to it.

the oil and the pan looks passable. i turned the motor by hand and sounded
good.
here are some pics of the lifters. don't know if the quality does good or harm to
describe the wear.
and the worst wear on the rocker.
what do you think?

 

[jzilla]

The wear on the cam is normal, due to not getting much oil at idle most likely. When reinstalling put a very light coating of Moly Grease on on cam lobes and lifters where cam and pushrods contact. Have the camshaft rebuilt and put in new bearings, the lifters might be able to be resurfaced as well.
That is what I did anyways...
Find a good shop and they should take care of that.