ClioSport.net

Register a free account today to become a member!
Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

  • When you purchase through links on our site, we may earn an affiliate commission. Read more here.

Removing 172 head - help/advice needed



  Track 172cup
I bought a 172 cup from a guy off here a couple of weeks ago with a suspected cambelt failure, instead of putting it into a garage for them to strip it down and tell me whats wrong i though i'd strip the head down myself and have a look and see what damage it's done (plus it'll give me a chance to learn a bit more along the way)

My intension is to diagnose what damage has been done and sell the engine on in bits or as a whole for someone else to play about with that knows more about what their doing, i'm looking at just replacing the whole engine

anyway i've started to strip a few of the easy bits off like inlets/plenum, fuel rail, airbox etc... but i'm left with the main cylinder head/block to contend with, as i've not done anything like this before and a bit of a newb any help/tips on how to go about this would be much appreciated

the only other thing i have done so far is drain the oil, all other fluids are still there.

if anyone could spare a few min to help it would be spot on, the main things that i am wondering where to go from here is how to actually get the head off from where i'm at the now and would it be ok to just cut the cambelt off to allow the head to come off as it's going to need new tensioners and belts anyway if someone was to fix it (remember i am just looking to diagnose the damage at this point) and how the hell do i get to it as the engine mount seems to make it ridiculous to get to around there

this is how it's sitting the now before i ran out of time and needed to pack up for the day...............

IMG_0911.jpg


IMG_0912.jpg


IMG_0916.jpg
 
  340i
Remove exhaust manifold...

Put jack/wood underneath sump..

unbolt main engine mount...

Remove cambelt / engine mount bracket...

As for the cam cover undo all the bolts, but then the cams are attached to that (and this is where I run out of skill ;))
 
Support the engine with a jack and remove the top mount...

Then you ideally need to get the engine to TDC, and lock the crank from the timing hole on the front with a 6mm pin. You also really need to lock the cams on the gearbox end, so you can undo the pullies.

IIRC the inlet pulley/cam will not come away from the rocker cover with the pulley still attached, so they really need removing.

If you have the cams + crank locked at TDC, with the belt still on, undo the pullies, then you can detension the belt and remove the belt from the pullies completely...

Then you can then remove the cam locking tool from the gearbox end, and undo all the bolts on the top of the rocker cover. Once they are all undone, remove the cover itself along with the cams etc.

You will then see the 10 headbolts down the 10 holes. Undo them in the correct order, then remove the head....easy as that, lol.
 
  Track 172cup
cheers lads, i was really hoping that i could remove the head without needing to mess about with the pullies etc... (basically so i don't need to buy the tools just to take it apart as i will definitely not be fitting a new cambelt etc.. myself as i'd rather leave that to a garage)

is there def no way of removing the head without doing all of this ?
 
  ITB'd MK1
first job would have been to take the top belt cover off to check if it's ACTUALLY a snapped belt. Last one i was told snapped a belt had actually drpped a valve
 
  Track 172cup
nice one cheers for the info, looks like i'll just need to get the tools ordered then, will have a search to find exactly what i need

danny all i've been told is that it's something to do with the cambelt so whether its snapped or skipped a few teeth then surely it's a case of checking the valves/pistons/bores anyway ?
 
  Track 172cup
I've not even attempted to start the car Fred, as it was an unknown I though it would be better to just get it stripped down and see what the damage was rather than risking causing more by turning it over

in hindsight maybe I should have ?
 
  Track 172cup
i'd try and turn it by hand

an idiots guide would be much appreciated if anyone has the time ;)

sorry i've got a very basic knowledge of engines atm and am just trying to learn a bit more the now so a lot of this goes over my head, you've got to start somewhere though eh :D
 
  Lionel Richie
nothing like starting at the deep end!

whack an 18mm socket on the crank pulley and try and spin the engine over by hand
 
  Trophy,R26,GSXR1000
If your knowledge is really basic, your best to remove the spark plugs first (as there'l be no compression to turn against. Also remove the top engine mount and lower the engine on a trolley jack so you can access the 18mm crank/aux belt pulley.

Then once you've rotated the engine several times and there's no mechanical restrictions. Try a compression test as previously mentioned.

If everything is still good change the cambelt and tensioner. You won't need the special tools to change the cambelt as you shouldn't need to slacken the pulleys (yes Fred+Danny we know it's good practice to). All you will need is the horse shoe cam locking tool and a crank locking tool.
 
  Track 172cup
nothing like starting at the deep end!


haha yeh i know mate, i've spent long enough reading about things and just thought it was about time i got my hands dirty, might aswell get stuck in as it's the best way to learn

cheers for the info Fred and Stevie it's much appreciated, i'll give that a go if i have time during the week, if not it'll be the weekend, and yeh Stevie my knowledge is very basic at the minute but slowly getting there haha

so will i still be able to get a decent compression reading by cranking it by hand ?

also i take it by just removing the top engine mount and dropping the engine a bit to get to the crank/aux belt pulley that it won't damage anything else along the way ?

cheers again gents ;)
 
  Clio Sport 172
Support the engine with a jack and remove the top mount...

Then you ideally need to get the engine to TDC, and lock the crank from the timing hole on the front with a 6mm pin. You also really need to lock the cams on the gearbox end, so you can undo the pullies.

IIRC the inlet pulley/cam will not come away from the rocker cover with the pulley still attached, so they really need removing.

If you have the cams + crank locked at TDC, with the belt still on, undo the pullies, then you can detension the belt and remove the belt from the pullies completely...

Then you can then remove the cam locking tool from the gearbox end, and undo all the bolts on the top of the rocker cover. Once they are all undone, remove the cover itself along with the cams etc.

You will then see the 10 headbolts down the 10 holes. Undo them in the correct order, then remove the head....easy as that, lol.

You shouldn't be locking the cams from the gearbox end to undo the pulley nut/bolts, if you are using the horseshoe locking tool you are likely to bend it. The cheapest place I have found the pulley locking tool is here:
http://ccw-tools.com/product.asp?strParents=&CAT_ID=9&P_ID=29228

or you can pay nearly double from Renault.
 
  Clio Sport 172
first job would have been to take the top belt cover off to check if it's ACTUALLY a snapped belt. Last one i was told snapped a belt had actually drpped a valve

I would do this first. Just support the engine, take the nut off the top of the upper engine mount and the remaining two bolts on the top cover (that piece connecting the engine to the engine mount) and you will see the top of the belt and weather it has snapped or not.

Then, if not snapped, try turning the engine.
 
You shouldn't be locking the cams from the gearbox end to undo the pulley nut/bolts, if you are using the horseshoe locking tool you are likely to bend it. The cheapest place I have found the pulley locking tool is here:
http://ccw-tools.com/product.asp?strParents=&CAT_ID=9&P_ID=29228

or you can pay nearly double from Renault.

I use the 6mm crank pin, the gearbox end tool (horseshoe), and the pully locking tool. All with the cambelt still in place, which takes some of the strain off the tools.

Also, I dont buy/use the cheap copy tools (Which are the ones that WILL bend, Laser etc.) I have the genuine renault items.
 
  Clio Sport 172
I use the 6mm crank pin, the gearbox end tool (horseshoe), and the pully locking tool. All with the cambelt still in place, which takes some of the strain off the tools.

Also, I dont buy/use the cheap copy tools (Which are the ones that WILL bend, Laser etc.) I have the genuine renault items.


OK, you didn't mention the pulley locking tool, and I have seen posts on here saying the horseshoe tool is crap because it bends, when it's purpose is only for cam alignment.
That one in the link is a Sealey tool in which I have full confidence.
 
  Track 172cup
cheers again for the info lads, can anyone shed any light on my other 2 questions i had above ?

so will i still be able to get a decent compression reading by cranking it by hand ?

also i take it by just removing the top engine mount and dropping the engine a bit to get to the crank/aux belt pulley that it won't damage anything else along the way ?

If i was going to do actually retime it and refit the cambelt and use the tool more than once then i would def buy the renault ones but i will literally just be using them to take this engine apart, can't really justify £100+ on tools for that
 
  Clio Sport 172
cheers again for the info lads, can anyone shed any light on my other 2 questions i had above ?



If i was going to do actually retime it and refit the cambelt and use the tool more than once then i would def buy the renault ones but i will literally just be using them to take this engine apart, can't really justify £100+ on tools for that

You will get some compression turning it by hand, but you won't get much of a reading on a gauge.

No,you won't do any damage supporting the engine and taking off that piece between the engine and the top mount. This will tell you a lot as you can see the part of the cambelt between the two cam pulleys.
 
  Track 172cup
so would it be best to try and crank it by the ignition then ? i have removed the fuel rail and injectors, would i need to refit these if i was to do it by the ignition ?

yeh cheers mate i was more wondering if lowering the engine would cause any problems with everything else thats still connected to it
 
  Clio Sport 172
If you want a proper compression test, you'll have to crank it with the ignition, but I would check to see if the belt is still in one piece first. That way you don't risk doing more damage if it is broken.
You don't need to lower the engine to check the belt, just support the engine weight while you take that top bracket off.
If the belt is on, then just lower the engine enough to turn the crank pulley, you will probably have to remove the sound deadening material that covers the crank pulley, if it's still there.
Once that bracket is off you can see how much you can lower the engine without the belt covers hitting the body, but from memory I don't think it's a problem.
 
  Track 172cup
cheers mangate and fred that's much appreciated mate, it's just a pity your so far away, fancy relocating to sunny scotland :rasp:

ok my plans for sat are:

support engine at the sump
remove top engine mount
check cambelt (if still in one piece and all tensioners/pulleys are fine do the following)
lower engine to access the crank pulley
remove all spark plugs
Refill engine with oil (i drained this at the start)
crank engine by hand to make sure everything is moving freely (if ok do the following)
compression test each cylinder - by ignition


just a couple more quick questions before i'm all set:

Am i ok to turn the engine over for the compression test with the engine as it is (no inlets/fuel rail) ?

As the fuel pump will be primed when the ignition is on will the fuel line (to the fuel rail) be ok to be left disconnected ?

and one final thing, what size thread is it for the spark plugs, did a search and there seems a bit of confusion between 10mm/14mm/16mm

found this compression tester and it's got 14mm and 18mm adaptors
http://www.screwfix.com/prods/16856...-Van and Car Accessories-_-Compression Tester#

Cheers again lads ;)
 
  Clio Sport 172
I'm not sure how the fuel pump will react on the Clio. I know on other cars I have had that you get a small squirt, then the pump is shut down as the ECM detects a fuel leak. You may have to pull the fuel pump fuse or relay, Fred?

As for spark plug thread, take a plug out and take it along to where you are buying the compresion tester.

You don't need to put oil back in while you turn the motor by hand as if you feel any mechanical contact such as valve to piston, then you wouldn't be able to do the compression test. If the engine turns by hand without any problem, then put the oil in before the compression test.
 
  Trophy,R26,GSXR1000
How about plugging the fuel line back onto the fuel rail but leaving the electrical injector plugs disconnected? That way the fuel system will be sealed.

As for the comp test just get the push and hold comp tester and get someone to turn it over while you hold it down?
 
You can ignore this post if you like ;)

But if it was me and i was going to swap the engine anyway, i'd remove it from the car and get it on a bench (or work on the floor/stand) You can still turn it over by putting 12v straight to the starter motor (for the compression test)

You'll find it easier getting access to the engine and performing the work you want to do.

Chris
 
  172 cup
^^^ man with a plan but does seem bit more of a mission to do that but then again alot more room to get a new cambelt on and suppose you would learn abit more about the engine being able to see it all properly
 
  Track 172cup
Mangate - cheers again mate, i'll keep an eye out for a compression tester with a long reach adaptor, i'm sure i seen one on machine mart earlier, that's where i'm getting an engine hoist from aswell (unless i find another decent one cheaper elsewhere) so might just order both from there

stevieh - sounds like a good plan cheers mate, i'll get on that and get the fuel rail back on

480bhp.com - don't be silly mate all hint/tips/comments are more than welcome, i'm always up for simpler ways of doing things ;) i didn't even realise you could still turn it over like that and it does sound like an easier way to do it but as my engine hoist won't come till next week at the earliest then i will hopefully have this done by then in the meantime, cheers anyway though bud

matty172cup - yeh mate it does sound like a decent plan and if i had got my finger out and ordered this engine hoist earlier i maybe could have lol, ah well


someones bound to know the thread size on the head for a spark plug ??
 
  172 gravel rally
Is the acc belt still in place? I have heard that if it jumps off this can make the cam belt skip. Could help diagnose a problem if the cam belt is still intact.

Good luck, just one more piece of advice that has always helped me is to label, bag and photograph everything that you take off the car, and where possible keep all bolts, nuts etc with the item you remove. Nothing worse than having a pile of nuts and bolts left over when you put everything back together.
 
  Track 172cup
Stakkabo - the aux belt is still there although it's sitting a fair bit to the side on one of the pulley/tensioners, i'll be able to have a better look when i get the top engine mount off

cheers mate, yeh don't worry i've labled every connector/wire/pipe that i have taken out aswell as put every bolt i've taken out into separate labelled boxes, sad i know but it's going to be the only way i keep track of it all :rasp:
 
  Track 172cup
So how did you get on? Interested to know wether the cam belt was actually broken.

sorry mate must have missed your post the other day, i've not even had a chance to look at the car since last week unfortunately, was away at the weekend and then i've been contending with man flu all this week, i'll update this as soon as i get my finger out

one plus is i got my compression tester and engine hoist delivered :D
 
  Track 172cup
well after a busy few months i finally managed to get my finger out and get a start on finding out whats up with this engine

got the top engine mount off and all the belts are still in place and not loose, managed to crank it over by hand and it moves freely, after doing that i thought i would check the inlet valves again for any movement before i went to compression test it and it's a good job i did as it looks like a couple of the valves in the first inlet have dropped lower down than the rest, the valves are still in tact with no obvious damage to them

anyone have an idea how/why this would happen and what other damage could have been done by this ?

Inlet 1 (showing the valves that have dropped)
Inletvalve1.jpg


Inlet 2
Inletvalve2.jpg


Inlet 3
Inletvalve3.jpg


Inlet 4
Inletvalve4.jpg


any help is appreciated as always ;)
 
  Track 172cup
ok thought i'd resurrect this thread instead of starting a new one

finally got some time and the space to get cracking with this but just trying to compression test the old engine before it comes out and having a problem with it even turning over

how the car is sitting at present - plenum/inlets, coilpack, ht leads and all associated connectors removed, fuel rail in place but without electrical connectors to stop any fuel spillage when cranking

the problem i'm having is when i go to crank it over it will crank for about a second then die

i'm using my Odyssey race battery to power it atm as the other one was completely dead, it's fully charged so i would have thought it would be up to the job for at least turning it over for a few seconds

either way it's coming out at the weekend whether i get it compression tested or not but would rather get it done so it gives an indication of whats up with the engine before i have to strip it down

any ideas ?
 
  172 Cup
i would say the bottom pulley has become loose and swung its self way out of time. Now im not 100% but in pic one it does look like the piston is at TDC sitting at the valves hence your cranking for a second problem.
 


Top