look my head cylinder

[chris971]

hi
look , this is my head cylinder of my pathfinder , the engine is dead , i buy a new engine


and this is my head cylinder of my navara , look the resurfacing on the valve lol , 100km after the reset , the engine it's hot ( view my other post )
what did you think ?

 

[tweak'e]

it looks like inlet valves have been hit
i would say timing was incorrect or head gasket to thin. ie didn't check piston height and select correct gasket.

 

[chris971]

the valve don't kissing the piston , but they haven't mark on here , but i think the resurfacing i'ts holy sh***

 

[tweak'e]

you think they skimmed the head with valves in place and machined the edge off the inlet valve?

 

[chris971]

yes they skimmed this with valves in place

 

[tweak'e]

do you know how much they took off?

you will need new valves and probably need to recut the valve seats to recess the valves in a bit. then reshim cam to valve.
or just get new head and valves.

 

[Old.Tony]

It does look like the head was shaved with ALL of the intake valves still in place. There are a lot of tool marks on the mating faces too.

The Pathfinder head also looks worse for wear. Is that a crack in the No4 cylinder exhaust valve? Is that a pitting (like a strike from a solid object pushed by the piston) between the two exhaust valves? It looks like the result of it swallowing a turbocharger.

 

[tweak'e]

The Pathfinder head also looks worse for wear.

it looks like the valves where hit. intakes valves have been pushed back into the port and are bent.

 

[Old.Tony]

By the look of the damage I'd say BOTH sets were hit. That crack could have started in the valve guide and that's an exhaust valve.

Pistons would show the other side of the story. I'm betting there are 4 nice dents in the crown.

It's actually not so easy to determine what's what without seeing in the ports, because Nissan changed the valve arrangements from the traditional inlet-valve-on-intake-side to the inlet-valves-in-front layout. Engine changes weren't always aligned between the D40 and R51.

 

[chris971]

for the navara , my new complete head cylinder AMC is arrived today , im verry happy

for the pathfinder , i don't know , juste the engine heat ..

 

[dilmah]

Do you recon you could measure the exhaust port size for me? Go a little project coming up that I need to know the size of the port for. Cheers

 

[chris971]

hi
you need size of exhaust exit head ? or exit manifold ?

 

[dilmah]

Head, Ill make my manifold to suit. Thanks

 

[chris971]

ok , tomorrow i can sent a message

 

[Hatchy]

Top head looks like it ate a turbo.