Cam 180 Degrees out symptons?

[Nickharding]

Had the cambelt snap about 4 days ago, picked up a new head gasket, Cambelt and some sealant, valves and pistons were fine so i rebuilt it back up following the book.. The bottom line on the pully was facing down to the ground (in line with the casing mark) and the line on the belt, and the mark on the cam pully was facing straight up and in line with the mark on the belt, nothing moved, all seemed well.

Car runs, but seems to only be running on 2 cylinders, now im not sure if its just my plugs giving up, as the 2 have a weak spark, which makes me wonder is it plugs or is it possible to have the cam 180 out?

Any advice will be great!
Thanks!

 

[CuppyDean]

Im sure a specialist will be long in a minute to help you but im pretty sure if you cam timing was out by 180degrees then you would have some broken valve and pistons

 

[Nickharding]

Nope, dont think so, this engine has enough clearance so when the belt does go, they dont meet.... Because that was exactly my first thought!

 

[CuppyDean]

As long as you know what you were doing and have the correct renault timing tools your timing should be correct, who carried out all the work?

 

[Nickharding]

I did,

Timing tools? On a D7F engine? you having a laugh? its only 2 marks and a simple tensioner! .. i just went by the book and all went well.
I think its just plugs tbh... as its getting spark but only a weak one.

 

[TheEvilGiraffe]

Timing tools? On a D7F engine? you having a laugh? its only 2 marks and a simple tensioner! .. i just went by the book and all went well.

TBF, you didn't specify which engine you are having issues with :boring:

 

[CuppyDean]

TBF, you didn't specify which engine you are having issues with :boring:

Exactly, i assumed an F4R engine, think he needs to be more specific next time

 

[Nickharding]

Whoops, sorry, didn't realise i didn't say!
Yeah engine was the 1.2 8V D7F engine, pretty simple thats why i didn't get tools.

 

[mx1_champ]

swap the 2 plugs around with the 2 bad plugs and see if the miss-firing cylinders now run on the better plugs.
could be a timing issue but sounds like something else to me

 

[Nickharding]

Well first thing i thought of was timing issue, but engine has been turned over MANY times now, and all the lines still match up etc, so dont think its that.
Yeah Will try that after i have had some food.
Cheers.

 

[MicKPM]

True, there's a lot of overlap on these 8v units but I'm sure you can't get the timing 180 degrees out on the D7F as the cam/cam pulley have a woodrough key so, if you're 100% sure the marks are in the right place then timing isn't the issue. If the pulley wasn't fitted properly to the keyway it would smash the pulley to bits when you tightened it up.

Mick

 

[MicKPM]

Delete me please

 

[sideways danny]

you'd struggle to get a cam 180 out turn the bottom end over once and it will be in the right place again. 1 cam rotation to every 2 crank rotations

 

[Nickharding]

Thanks Mick - Deffo on the key properly, made sure of that! i hope its just plugs!

Ah right, Cheers dan, i guess thats why you have to do 4 crank rotations to get the lines to line up again because its a "Four Stroke"

Will let you know about swapping the plugs later.

 

[Nickharding]

About to try new plugs now, will let you know shortly.

 

[Laine_16v]

You didnt replace the valves by the looks of things, chances are they are now leaking even if they look fine. If you did replace the valves then ignore

 

[Nickharding]

Nah, i redid the timing today and exactly the same fault, so gonna get the head off tomorrow and do a leakdown test. Cheers.

 

[MicKPM]

Did you not think to try a spare plug in the end of each lead first to see if they're all sparking? Also, why not just carry out a compression test first before removing the head?

 

[Nickharding]

I knew they were all sparking, and wanted to remove the head to make sure everything was alright, only cheap parts for it anyway so didn't mind.
Found out tonight after a strip down i got 2 bent exhaust valves, hoping to have it running again tomorrow.

 

[Nickharding]

Was the 2 valves, all built up again, Rocker gaps re-set, runs like a new engine now.

 

[MicKPM]

Doh! Oh well, all done and running again now. It always pays to have that pressure check carried out before replacing a head with valves that look okay

 

[Nickharding]

Yeah deffo.
I have a compression tester but let my mate borrow it, was quicker to build it up, try it, and if it failed strip it down and fix it, than to wait for him to get it back to me.
Least its going again now.
Sounds so much nicer now i done the gaps ontop too.