Lancer Register Forum banner

4g63 evo 6 dropped valve.

16K views 88 replies 18 participants last post by  stevov 
#1 ·
Hi all,

Does anyone know where I can find a step by step guide to take my engine apart so I can change a possible dropped valve?

Preferably with pictures. I'm more of an intermediate with vehicle repairs. However, never stripped an engine before (let alone the one in my baby)

I have had a few quotes from garages etc. And figure its all mechanical so as long as I follow a guide to the letter I sshould be ok and save £££'s.
Just not to sure where to start? ?
Any help would be greatly appreciated.
 
#4 ·
Clearly stupid noob questions but I would rather ask....
1. Do I drain the oil first (im thinking yes?)
2. Is it easier removing the drivers side wheel and arch liner to access the pulleys etc?
3. With the icy snowy weather do I need to be concerned about liquid ingress to the engine? Will a simple coverbe ok once its all apart?

Sorry if it seems like stupid questions to you all but I have to learn somewhere.
 
#6 ·
I realise it will be straight in but usually if I have the instructions or a general idea im ok.... the mechanic that recovered me said based on the clicking noise it was making, followed by the clunk after it died. Then seemed to of seized (won't crank) obviously until it is stripped this can't be confirmed but speaking to several garages they all seem to come to the same conclusion of possibly a dropped valve.
 
#10 ·
I have taken the plugs out and rocker cover off but cannot see anything out of place (although arent the valves etc. On the under side (on top of pistons) so I wouldn't be able to see damage if any without taking all the cams out
 
#11 ·
Not being funny but I dont think its a good idea you attempting this yourself. If you have dropped a valve and the engine is completely looked up chances are you have probably done some serious damage.
Pull all the plugs and attempt to turn the engine over by hand, If you have dropped a vale looking down the plug holes you would probably be able to see some signs of damaged. Have you drained the oil or removed the cam cover to check for signs of damage?
 
#14 ·
Any feedback is always a help. I realise may not be the best idea but I have already resided to the fact new block is worst case scenario just figure if I can sort it myself why not if it does all go wrong then I get a new block put in.
Top cover is off and all seems ok comparing to various pictures oil will be drained tomorrow.
 
#20 ·
Think you could be a bit out of your depth with this m8.

I've changed clutches,a few headgaskets etc...on my Renault 5 turbo in the days.

But wouldn't tackle taking my Evo engine apart.

Get it to a professional m8,do your homework on who to take it to,otherwise you could end up with a car on your drive.

And the hardest jigsaw puzzle to put back together ever..

Hope you get it sorted :smthumbup
 
#22 ·
Thanks for all thw replies all greatly appreciated, I have been let down with a trolly jack to get the wheel off and get to the crank properly.
Taken the cam cover off again and now I have an idea what im looking at thanks to the manual. All springs etc.Seem to be seated correctly.
It would appear the cam belt has slipped quite a bit, from what I can see at the moment the crank sprocket has jumped a couple of teeth and also the exhaust side cam has jumped about 3 teeth according to the timing marks on the sprockets.

So obviously at the moment timing needs rectifying and new belt.
Possibly bent the valves?
 
#23 ·
from what you have said above you should
- remove and put the belt back on correctly (may have to turn the bottom end backwards by hand and try to turn cams by hand to allow for movement as it sounds like you have a piston touching a valve atm)

- try to turn engine over by hand at least 2-3 turns to see if it moves freely by hand

- if turns over fine remove ht leads and turn engine over using starter motor

- if it turns over by starter motor then do a compression check to check all cylinders have equal compression

- if compression check is ok re connect the HT leads and try to start it.

FINGERS crossed for you but it sounds like you may have a few bent valves in their.
 
#24 ·
Thank you very much "rob2.2" this seems a lot more promising and cheaper than I was originally expecting.
Providing I get past the compression check and it starts all ok, can I presume its drivable?
Or worth changing the valves anyway?
 
#25 ·
if you have the correct compression on all 4 cylinders, try starting it , if it runs fine their is no reason not to drive it and go buy a lottery ticket as luck is on your side.
 
  • Like
Reactions: BrooksyVI
#28 ·
I have ordered myself a 3t trolly jack now. Although have to work now till a week Saturday. However, if I can get it on stands before then and check all this out I will and update here. Thank you all some perfect information and could possibly saved me £££'s
 
#29 ·
Had my lifting kit delivered today, its up on stands took rocker (cam) cover off plugs out (found the end of one plug to be completly broken off - nearest the camshaft sprocket) slowly turned the crank and on inspection inside this chamber I can see what looks like 3 valves sat on top of the piston.

So I guess I need to take all the belts off and the cylinder head to get and see exactly how much damage is done?
 
#39 ·
Mate that's proper shagged. Sorry to say! You will need a new piston and the bores/crank inspecting and that's just the start. Would be cheaper to buy a replacement engine and drop it straight in IMO.

Was the oil clean when you drained it?
 
#40 ·
So far only cost around £200 doing it diy so much cheaper (tools, new cylinder head, cams, valves, lifters etc.) Im looking around £1300+ for an engine roughly? ...... totally forgot about draining the oil! Will get to that asap..... im expexting some debris in there will strain it and post pic when I have it.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top