Bad knock Help!!!!! asap

[jimmi308]

just purchased a 99 expedition e/b 5.4l have a very bad knock just off idle. had a different motor installed this feb (po had this done) 135,*** miles... motor just started to knock and po was told it was the trans... noise seems to be comming from passenger side top. got a very good deal on this... any help on this would be GREATLY appreciated

 

[walnuts4x4]

i don't know exactly the problem but try to give some more details... but have you checked the COPs and spark plugs... it could be a spark plug is getting ready to blow out or already did... but give us some more info or post a pic and more people will chime in and try to help

 

[jimmi308]

not really sure what more there is... no cel, if a plug blew off it would be missing?, right? everything looks good.... had some oil comming out of tail pipe, but vehicle has been sitting a few weeks.... sound is very loud like a hammer on a big chunk of aluminum.... and rises with engine speed.... also should any of the cop seem loose at all?

 

[nvycrmn]

sounds like exhaust leak that could cause the ticking. does it go away or quiet down when the engine is warmed up?

 

[alexhozee]

Hard to tell, nothing more difficult than to describe a sound
Maybe a broken valve or bearing?

Do you have any powerloss?

Does the nois has the same rpm as the engineand does it, don't know how to say this in english, like you hear the rpm go first and the sound comes a couple of seconds later.


Same when you step on the pedal let the rpm go to like 4000 rpm and let go of the gas, does the noise get any louder when you do that?
if so I would say the mean bearings/crankshaft bearings.

Good luck!!

 

[2blackfordrides]

If it is that loud probably a spun bearing... I have my 99 xlt with a 5.4 apart now,,,, was sitting at a light at idle when the engine started to stumble, no check engine light or ne thing....truck had been sitting for 6 months before i bought it..... Pulled the oil pan and low and behold.... Spun rod bearing on 8th cylinder...... Bearings arent that expensive.... Like 4 dollars a piece but have to watch to see if there was any damage to crank.... You may have to install a oversized bearing if it is a spun bearing.and check oil clearance with plastiguauge.... If it damaged the crank, u may think about a new motor just cuz its a pain from what im told..... Not for sure this is what it is for you but sounds just like what happened to mine...... Let us know how u make out.... The guys on here know their stuff and know it well..... Sure u will find a solution.....

 

[jimmi308]

Ive been working on cars and trucks forever but new to these tritons.... wife has an 01 xlt which runs awsome. kinda why Im selling my bronco in favor of this new truck. have to post some pics of both or rides.... but any ways yes the noise does rise and fall with rpm... but noise seems to lags behind rpm kinda. as far as I can tell noise is only passenger side, towards the top...

 

[jimmi308]

well dropped off at local shop. just by hearing it tech said sounded like a loose torque converter bolts or loose or broken flex plate. will post what I find out tomorrow..... im crossing my fingers its something that simple.... but that just aint my luck....

 

[ghettoracer]

BTW a blow out is bad on your triton, can strip the plug hole and take out your coil on plug real quick, it will sound like a bad exhaust leak if it did do the notorious "Blowout".

 

[jimmi308]

checked all the plugs they are good.... this is way more than an exhaust leak will find out more when the shop calls me today.... will post results as I find out

 

[jimmi308]

bad news.... no 8 cyl rod bearings gone..... so much for a good deal.... least po wrote on sales slip that motor was free of defects... so he will be paying at least half of the replacement cost....

 

[gijohn45]

my 98 as a similar sound but I found it coming from the A/C compressor... its a thump thump thump sound and when looking at it with a timing light you can see the front drive belt actually raise up....

 

[cpski2b]

Question

Jimmi308,

Did they resolve the issue with just a bearing or did it damage the crank? If you don't mind me asking, what did they charge to fix it? I may be in the same boat.

Thanks,
Craig

 

[jimmi308]

yea... #7 and 8 rod ends just wasted. 1/4 in of slop in them.... just had a different motor installed(very long and retarded story...lol).... going to rebuild it though..... need to get pics of mine and my wifes trucks on here......