Broken timing chain extent of damage

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Azi

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Hi I have replaced timing chain ( completely broken ). Replaced 2 valves no 1 cyl. Visually pistons top looked ok . Cleaned out sump and pick up.
Started the motor and bummer...3 problems
1 constant loud knock ( rattley when reved up.
2 slight misfire
3 oil light flashing. ( I was very carefull with o rings while refitting t case cover )
Wondering if no 1 piston could have damge near the pin ., Almost sounds like con rod bearing gone
Anyone has had damage apart from bent vavles
 
There's additional damage you might consider being at risk of there.

With bent valves, you KNOW there's been considerable pressure applied to the piston/gudgeon/conrod/big end and maybe even the main bearings.

Up top, a bent valve may indicate valve guide damage, and even camshaft bending or bearing damage.

There's certainly a lot to check over to ensure the engine is ok.
 
Hi Tony,
Cyl head was done and checked at head shop.
I only finished work on it yesterday. Will do more checks this week.
I was hoping bottom end and piston would be ok. Only 2 valves were bent in No 1 cyl.
Noise seems to be around no 1 cyl.
If I dont find anything obvious then I will have to remove motor and remove piston and inspect it
 
Hi. If u have a misfire, check compression especially on no 1 cyl. I take it u reseated the valves on head. Don’t take much for a diesel to lose enough compression to run rough. Checked injectors??
 
Having just rebuilt mine due to a broken crank, i am really surprised that the only damage was 2 bent valves in number 1 cylinder,

With the knocking, as mentioned do a compression test and go from there, worst case you would want to look at #1 piston and rod, ( i would look at 4 as well, they are at tdc at the same time although the firing order i think is 1243)
 
Hi, thanks for help fellas. Yes , I did a compression test ( cold engine ). It is ok, 380,400,400,380.
I suspect No 1 injector. I bought vehicle with broken chain. It was parked for 4 years with injector pipes off and not covered.
Oil light has come good. No flashing and goes off when engine running.
Con..how do you break a crank ??
 
Hi, thanks for help fellas. Yes , I did a compression test ( cold engine ). It is ok, 380,400,400,380.
I suspect No 1 injector. I bought vehicle with broken chain. It was parked for 4 years with injector pipes off and not covered.
Oil light has come good. No flashing and goes off when engine running.
Con..how do you break a crank ??
Haha 365000k, when i got it apart 1 bolt on the #4 main cap had completely backed out, and was only held in place by the balance shaft housing, i also figure it had been like that a long time before it broke, it also seemed that it ran for a while like that, it was making a funny noise i could make go away by giving it a little clutch pedal, but went around a corner and was accelerating out and it went bang and stopped, fortunately the ecu picked up the difference between the crank angle and cam angle sensors and shut it down, crank was the only damage (and the previously mentioned later found cracked head) coincedentally during this process i dont think i was the first person to be inside this engine, different coloured formagaskets and a few other subtle signs...... the car had 150k on it when i bought it

As for a bad injector its easy to find if you have one of those infrared laser thermometer, the exhaust manifold will be significantly colder at the cylinder with a dead injector, i went through this with mine as well, and it did run like absolute crap, as rough as when the dual mass flywheel failed

In my instance i ended up doing the full set of injectors, (15k before the crank snapped)
 
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Haha 365000k, when i got it apart 1 bolt on the #4 main cap had completely backed out, and was only held in place by the balance shaft housing, i also figure it had been like that a long time before it broke, it also seemed that it ran for a while like that, it was making a funny noise i could make go away by giving it a little clutch pedal, but went around a corner and was accelerating out and it went bang and stopped, fortunately the ecu picked up the difference between the crank angle and cam angle sensors and shut it down, crank was the only damage (and the previously mentioned later found cracked head) coincedentally during this process i dont think i was the first person to be inside this engine, different coloured formagaskets and a few other subtle signs...... the car had 150k on it when i bought it

As for a bad injector its easy to find if you have one of those infrared laser thermometer, the exhaust manifold will be significantly colder at the cylinder with a dead injector, i went through this with mine as well, and it did run like absolute crap, as rough as when the dual mass flywheel failed

In my instance i ended up doing the full set of injectors, (15k before the crank snapped)
Very cleaver trick with the temp gun on the manifold, danmmm smart.... And to snap a crank, wow! First I've ever heard of one doing that...
 
Hi, thanks for help fellas. Yes , I did a compression test ( cold engine ). It is ok, 380,400,400,380.
I suspect No 1 injector. I bought vehicle with broken chain. It was parked for 4 years with injector pipes off and not covered.
Oil light has come good. No flashing and goes off when engine running.
Con..how do you break a crank ??
Take the oil pressure sender switch out and clear that oil gallery out by turning the motor over and then re fit... if you're having oil light issues try this... the oil in that dead end oil gallery turns to mud and ruins the sender unit or prevents it from working at its best.. cheers
 
great story. Sorry for late response fellas.
I isolated each injector by disconnecting connector ( with motor running ) the noise would go away on No 1 .
Just to be sure I swapped injectors..1 and 3. No3 became noisy, so I was convinced it was injector.
After a lot of youtube and other reputable sites, I decided to open the injector bottom end and cleaned out nozzle and long pin ( all looked ok ). put it back in car and she was still the same..bad knock and misfiring. This was last week, I thought damn I will be up for set of injectors, programming etc.
Today I decided to pull the top section as well as bottom. cleaned it out ( coudn,t see any dirt etc ). Half heartedly assembled it and installed in car.
Started and the knock and misfire has gone. She is running beautiful and smooth.
As far as calibration, I dont think it has changed because nothing has been replaced in injector.
 
Hi Tony, just with carby clean spray. You need the tube to spray into nozzle and see if all holes are clear in nozzle.
In my case I was expecting foreign material and not worn injector because it was parked with injector pipes removed and not covered for 4 years.( thats how I bought this vehicle ).
I used carby clean , then compressed air, then carby clean only. Assembled with clean diesel.
I think if you dont replace any parts ( nozzle etc ) then you wont alter the calibration. This is my opinion only, Im no expert, and its the first time ever I have pulled an injector apart.
regards
 
Sounds great, it's what I'd do first. Brushes/files/anything solid could damage the surface and change spray pattern or volume (which would more likely cause a leak given the pressures behind it).
 
Agree with Tony, thus is a great result,

Will file this little tidbit into the file for later

Congrats,
 

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