timing chain and head gasket

[nathanmoris]

i have a ka24e timing chain that broke and i was wondering if it was just a straight replacment or becuase it broke i have to check other things? i also was wondering what causes loss of power.. the head gasket was recently replaced and after that change it loss power. the compression in all cyclinders are fine. could it had been a bad head gasket replacement? any help would be great thanks jon

[rotorimp]

Nissan chains do not break that often and is most likely related to the head gasket replacement. If you experienced a loss of power right after the hg change then the timing might have been off. How are you able to test compression if the chain is broken? If the chain did break then most likely you have bent valves. Are you sure that the chain is broken?

[nathanmoris]

im sorry i should have word it correctly.... the chain it self didnt break but the timing chain sproket on the crank broke off where the chain is connected.... does this still mean that i need to replace valves since i bent them or could i just replace it and ill be fine thanks jonathan

[180fan]

won't know till you pull the head.

[nathanmoris]

is it just a visual thing to see for bent valves or do i have to take apart the head more to see the valves? thanks jonathan

[180fan]

just pull the head and if you see scoring on the pistons that'll be another clue. remember to rotate the cam as well. or with the head still on, pull the manifolds, and loosen the cam towers so all the valves should be in a closed position. with compressed air, shoot it through one side of the head. if air passes through to the other side, you've got a leak.

[rotorimp]

Can you still rotate the motor? I have also never seen that sprocket break. 180 is right--tear that head off and see whats going on in there.

[wa-chiss]

hold on. I thought the KA24E was a non-interferance engine. So even if the chain broke, the piston shouldn't hit the valves. Please, correct me if I'm wrong.

[rotorimp]

They are DEFINITELY interference motors--

[480sx]

For sure lol, your wrong. A jeep guy tossed that term at me the other day and i was trying to throw around the idea in my mind..

What OHC motor ISNT an interference motor...

[rotorimp]

Since you asked--mazda miata

[nathanmoris]

so since my timing chain broke while i was on the fwy i problay need to the head off and change valves right

[rotorimp]

Yes.

[nathanmoris]

hey, i dont have the money to get a ka24e head rebuild or a new one.. so i was going to buy a used one from someone. i was wondering what i could check for the i can see i guess to make sure its ok if theres anything thanks for any help jonathan

[rotorimp]

Most importantly make sure that the head is flat--go to a machine shop they will not charge much. then follow the procedure in the fsm. Good Luck

[nathanmoris]

Thanks

[jaytv1019]

I have 2 KA heads. Let me know if you need one.

[nathanmoris]

yeah i do ... are they in good condition and everything and how much you want for them if so and where are you located

[nathanmoris]

hey so since the chain broke i did mess up the valves but the small block and pistons and all that is fine right? cause i gonna try to get some work on it done but i dont want to spend money on it if the pistons to are messed up thanks for the help

[rotorimp]

You will have to pull the head--I have seen only 1 valve messed up and I have seen holes in pistons. So pull that head and see what is damaged.

[nathanmoris]

i got a bent valve after pulling it and the pistions look good to me but really what do i know about pistons... nothing..... theres no movement from side to side and no damage to the cylinder and a little dark pistons but i think thats from combustion.... anything else im missing about the piston check... thank alot rotorimp you know a lot and i am very greatful for all this info thanks

[nathanmoris]

hey, im having trouble removing the intake manifold from the head, i made sure all the bolts and plates are off the head but when i try to split it i dont nreally seem to be getting it apart.... is it just really hard or is there a secret to this i dont know thanks

[180fan]

give it a wiggle. Did you also get the hoses and wiring off?

[wa-chiss]

How many bolts did you remove? There are 7 IIRC. Two run through the manifold. It took me a while to figure it out. Yeah I felt dumb.

[nathanmoris]

Thanks Everyone finally got it off..... since i had a bent valve ... would that cause the loud ticking, knocking noise under the valve cover ... thanks jonathan

[rotorimp]

Let us know how it turns out--post up some pics. so we can see the carnage. Good luck!!!

[pmb434]

Just had the same thing happen to my ka24de broke the cam bent all the intake valves still trying to get it together good luck my pistons had some marks on them but was ok if you learn short cuts or good info please post it .