Jump to content

Intake cam failure - valves and pistons look good?


PabloVC

Recommended Posts

Hey people,

 

A while back, my HR died on me. 

 

Cruising on the motorway in 6th when I suddenly lost power. No grinding, no horrible noises, just loss of power. No engine management light either.

 

Next day, it would start but only on 1 bank.

 

At first I thought it was the Cam Position sensor as it did eventually give me an engine light and indicated the camshaft position sensor. Bought brand new Nissan OEM sensors (replaced all of them). Still the same. 

 

Checked fuel, fuses, wiring, etc. Noticed my spark plugs had a bit of oil on them so I replaced the rocker covers. Checked the cams themselves for any obvious damage. Everything looked good.

 

So... timing chain?

 

Eventually, I took the cam timing chain cover off and inspected it. All looked good. Turned the crankshaft. All looking good.

 

Until I eventually noticed (through my oil filler) that my intake cam wasn't turning!

 

So yeah. Intake camshaft broken. Took the rocker cover off and inspected it again. No damage there! The damage is right by the camshaft sprocket!

 

I guess, what I'm asking is... Should I fix?

 

I can't do a compression test. I can't put the chamshaft timing cover back on because the sprocket isn't sat where it should be anymore. I can't do a leakdown test as I don't have a compressor and no real means of having one either...

 

However, my intake valves all look good. Due to where the camshaft snapped, all the valves are in the highest position and fuel was collecting behind them. Used my beroscope down the spark plug holes and looked at the pistons. From my limited knowledge... They look fine.

 

I'm a little bit hesitant to buy a new camshaft (would a used one be a bad thing to do?) and hope for the best without getting some thoughts from those far more knowledgeable than me!

 

I feel like it would make sense to do the timing chain, water pump and gallery gasket(it has been done before, but considering it's just there and it's a £20-£30 part)) since it's done circa 190k if I was to do it all...

I'd rather do the work myself as money is a bit tight! Fairly competent. Did my entire clutch system last December when the CSC failed 😅

 

Or should I actually take it to Horsham/Japex, etc and get it looked at properly... Just money is tight atm!

 

Thanks in advance for any help!

 

This is it starting before I took the cam timing cover off

 

Vids of the pistons...

 

20221029_165357.jpg

20221120_171350.jpg

20221120_171401.jpg

20221120_171410.jpg

20221120_190503.jpg

Edited by PabloVC
Link to comment
Share on other sites

  • 2 weeks later...

Well that sucks !
But you're kind of lucky too in some respects.

You're only going to know the state of the heads & parts once it's taken off, and checked over for leaking/bent valves (plus checking pistons for any contact).
Ideally you want to know exactly what caused the failure, rather than just blindly replacing bits and pieces.
At 190k miles, yes definitely replace all of the timing stuff, water pump, and at least strip and clean/inspect the oil pump too if you're going to keep this car.
No harm in replacing the cam with a good used one.

If you're going to do it yourself, you'll definitely need a decent selection of tools, some cover and you're going to need to have the heads resurfaced and valves checked/cleaned by a professional.

So yeah, either fix it yourself (and get the right tools), get someone else to do it, or sell it as is and take the hit.
🤕

Link to comment
Share on other sites

Awful but lucky to not of had piston to valve contact. Did well to diagnose the broken cam, doubt I would have found that. I wouldn't replace the gallery gaskets if already been done, as the part should have been the uprated items.

 

Good condition used cam I would use.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...