Loctite 518 equivalent/replacement...
Discussion
Refitting the cylinder head after cambelt breakage on a 1.4, 16v Renault engine, manual calls for Loctite 518 on valve cover/bearing cap seal (no gasket).
Not wanting to fork out for yet another expensive sealant that I'll only use a small amount of, I was wondering what could be used instead? Especially as I have a selection of various sealants; to hand; Dirko HT, Stag Wellseal, Threebond 1215, Threebond 1104, Loctite SI 5980 and Hermetite red.
I'm thinking probably the Dirko HT due to oil resistance/high temp (315 c) is probably the most suitable as previously used on core plugs with no bother but don't want any failures so will buy the 518 if essential, any advice?
TIA.
Not wanting to fork out for yet another expensive sealant that I'll only use a small amount of, I was wondering what could be used instead? Especially as I have a selection of various sealants; to hand; Dirko HT, Stag Wellseal, Threebond 1215, Threebond 1104, Loctite SI 5980 and Hermetite red.
I'm thinking probably the Dirko HT due to oil resistance/high temp (315 c) is probably the most suitable as previously used on core plugs with no bother but don't want any failures so will buy the 518 if essential, any advice?
TIA.
280E said:
I used the 'correct' 518 on mine. Why risk compromising the joint - it's a relatively small price in the overall cost of the job.
The other sealants you mention are not anaerobic-curing types.
What he said.. Anaerobic sealants are used for a good reason as they only cure inside the joint, any excess is washed away pretty much harmlessly. Silicone based sealants tend to squeeze out the excess and this cures inside the engine void, it’s inclination is to shed into the engine void and accumulate in the sump where it inevitably ends up partially blocking the oil pickup.. I see this all the time, in a few cases rod bearing failure results.The other sealants you mention are not anaerobic-curing types.
Dave
Interesting, not done it yet so will look into something more suitable.
One thing regarding the Clio though for anyone who's done it before: As the belt broke in service and head has been removed, valves changed etc (ex valves were all bent). I don't have the reference of the position as you would if just changing a good belt.
I have the cam and crank locking tools and understand how to use them i.e. cyl 1 to TDC, cams held by the clamp but is it important which TDC? as I see it it could be on compression TDC or exhaust TDC and I have no way of knowing which - how does the engine 'know' which and more importantly how do I know? Mechanically with regards to piston to valve it would be fine but if it fires/injects on the wrong stroke it's not going to run - am I missing something?
Also, WTF the crankshaft pulley not being keyed to the crank - timing relies solely on the bolt being tight!!
One thing regarding the Clio though for anyone who's done it before: As the belt broke in service and head has been removed, valves changed etc (ex valves were all bent). I don't have the reference of the position as you would if just changing a good belt.
I have the cam and crank locking tools and understand how to use them i.e. cyl 1 to TDC, cams held by the clamp but is it important which TDC? as I see it it could be on compression TDC or exhaust TDC and I have no way of knowing which - how does the engine 'know' which and more importantly how do I know? Mechanically with regards to piston to valve it would be fine but if it fires/injects on the wrong stroke it's not going to run - am I missing something?
Also, WTF the crankshaft pulley not being keyed to the crank - timing relies solely on the bolt being tight!!
catso said:
Interesting, not done it yet so will look into something more suitable.
One thing regarding the Clio though for anyone who's done it before: As the belt broke in service and head has been removed, valves changed etc (ex valves were all bent). I don't have the reference of the position as you would if just changing a good belt.
I have the cam and crank locking tools and understand how to use them i.e. cyl 1 to TDC, cams held by the clamp but is it important which TDC? as I see it it could be on compression TDC or exhaust TDC and I have no way of knowing which - how does the engine 'know' which and more importantly how do I know? Mechanically with regards to piston to valve it would be fine but if it fires/injects on the wrong stroke it's not going to run - am I missing something?
Also, WTF the crankshaft pulley not being keyed to the crank - timing relies solely on the bolt being tight!!
Simply put.One thing regarding the Clio though for anyone who's done it before: As the belt broke in service and head has been removed, valves changed etc (ex valves were all bent). I don't have the reference of the position as you would if just changing a good belt.
I have the cam and crank locking tools and understand how to use them i.e. cyl 1 to TDC, cams held by the clamp but is it important which TDC? as I see it it could be on compression TDC or exhaust TDC and I have no way of knowing which - how does the engine 'know' which and more importantly how do I know? Mechanically with regards to piston to valve it would be fine but if it fires/injects on the wrong stroke it's not going to run - am I missing something?
Also, WTF the crankshaft pulley not being keyed to the crank - timing relies solely on the bolt being tight!!
Tdc is tdc. The valve setting sets the correct position for induction or exhaust. So if all the timing tools are in place correctly, then the engine is timed as it needs to be.
As for non keyway pullies, it is the modern way. Stupid in my idea. Make sure everything is clean and dry. It relies on friction to stay in place. A keyway is much simpler and safer, but probably costs more at manufacturing level.
As regards the sealant. Instant gasket (various makes of it) is designed exactly for joints like the 1 on your engine. Loctite is good, and it works well. Is it essential? Not in my opinion or experience.
Coilspring said:
Simply put.
Tdc is tdc. The valve setting sets the correct position for induction or exhaust. So if all the timing tools are in place correctly, then the engine is timed as it needs to be.
Thanks was hoping so, it must get the timing signal from something cam related then?Tdc is tdc. The valve setting sets the correct position for induction or exhaust. So if all the timing tools are in place correctly, then the engine is timed as it needs to be.
But not keen on the non-keyed pulley, suppose it must work well enough but it just isn't right IMO.
catso said:
Thanks was hoping so, it must get the timing signal from something cam related then?
But not keen on the non-keyed pulley, suppose it must work well enough but it just isn't right IMO.
Usually a combination of crank and cam angle sensors.But not keen on the non-keyed pulley, suppose it must work well enough but it just isn't right IMO.
But the valve timing is set to the crank by belt/chain so the camshafts rotate in sequence.
A few questions:
Has the cylinder head been re-fitted yet?
Do you have the correct tool to hold the camshaft sprockets whilst their retaining nuts are tightened?
Have you got new cam sprocket nuts and a new crankshaft pulley bolt?
Will you be changing the auxiliary belt at the same time?
Do you fully understand how to use the timing tools (crank pin and camshaft 'horseshoe')?
Does the 1.4 engine have a VVT inlet pulley? (I don't think it has).
What model year is the engine?
What is the airspeed velocity of an unladen swallow?
Has the cylinder head been re-fitted yet?
Do you have the correct tool to hold the camshaft sprockets whilst their retaining nuts are tightened?
Have you got new cam sprocket nuts and a new crankshaft pulley bolt?
Will you be changing the auxiliary belt at the same time?
Do you fully understand how to use the timing tools (crank pin and camshaft 'horseshoe')?
Does the 1.4 engine have a VVT inlet pulley? (I don't think it has).
What model year is the engine?
What is the airspeed velocity of an unladen swallow?
280E said:
A few questions:
Has the cylinder head been re-fitted yet?
Do you have the correct tool to hold the camshaft sprockets whilst their retaining nuts are tightened?
Have you got new cam sprocket nuts and a new crankshaft pulley bolt?
Will you be changing the auxiliary belt at the same time?
Do you fully understand how to use the timing tools (crank pin and camshaft 'horseshoe')?
Does the 1.4 engine have a VVT inlet pulley? (I don't think it has).
What model year is the engine?
What is the airspeed velocity of an unladen swallow?
Yes (but not cam cover)Has the cylinder head been re-fitted yet?
Do you have the correct tool to hold the camshaft sprockets whilst their retaining nuts are tightened?
Have you got new cam sprocket nuts and a new crankshaft pulley bolt?
Will you be changing the auxiliary belt at the same time?
Do you fully understand how to use the timing tools (crank pin and camshaft 'horseshoe')?
Does the 1.4 engine have a VVT inlet pulley? (I don't think it has).
What model year is the engine?
What is the airspeed velocity of an unladen swallow?
No
No/Yes
Yes (also replaced alternator bearings as they were noisy)
Yes (although not 'found' the hole for the locking pin yet)
No
2007
African or European?
African or European? I don't know that!....
The first thing I'd do is bring the pistons somewhere near mid-travel with cyls 1&4 on the upstroke - this allows you to rotate the cams without fear of valves kissing the pistons.
Once you've re-fitted the cams and cover, the cam sprockets need holding in place with a 'special tool' whilst the retaining nuts are tightened. As with the crank sprocket, the cams aren't keyed to their sprockets - relying pureley on clamping friction from the fixing nut. The contact surfaces should therefore be cleaned thoroughly with, say, brake & clutch cleaner before assembly with new nuts. The nuts are done up pretty tight (torque + angle), and there is a risk of breaking the cams if you just rely on the 'horseshoe' setting tool in the far end - hence the sprocket retaining tool. Obviously, the 'horseshoe' needs to be fitted along with the retaining tool.
The slots in the cams are offset from centre, and the 'horseshoe' MUST be fitted so that the slots in the cams lie below the centre line.
The plug for the crank setting pin can be a bit hard to access, and will require a female torx socket if original. The pin doesn't actually 'lock' the crankshaft, but stops up against a machined web on the crankshaft. Pistons 1&4 are brought to, say, 15 degrees BTDC - then insert the pin and screw in fully. The crank is then rotated nice and slowly until it *just* contacts the pin - this is TDC.
The pin can be left in place even for the final tightening of the crank pulley bolt . Again, degrease the contact surfaces thoroughly, use a new bolt, and it's another torque + angle affair.
The timing belt tensioner needs setting carefully - with all tools removed, turn the crank by at least two revolutions to 'settle' things and re-check the indicating pointer.
Good on you for replacing the auxiliary belt - this often fails with the debris getting into the timing cover and mangling the timing belt!
Have fun!
The first thing I'd do is bring the pistons somewhere near mid-travel with cyls 1&4 on the upstroke - this allows you to rotate the cams without fear of valves kissing the pistons.
Once you've re-fitted the cams and cover, the cam sprockets need holding in place with a 'special tool' whilst the retaining nuts are tightened. As with the crank sprocket, the cams aren't keyed to their sprockets - relying pureley on clamping friction from the fixing nut. The contact surfaces should therefore be cleaned thoroughly with, say, brake & clutch cleaner before assembly with new nuts. The nuts are done up pretty tight (torque + angle), and there is a risk of breaking the cams if you just rely on the 'horseshoe' setting tool in the far end - hence the sprocket retaining tool. Obviously, the 'horseshoe' needs to be fitted along with the retaining tool.
The slots in the cams are offset from centre, and the 'horseshoe' MUST be fitted so that the slots in the cams lie below the centre line.
The plug for the crank setting pin can be a bit hard to access, and will require a female torx socket if original. The pin doesn't actually 'lock' the crankshaft, but stops up against a machined web on the crankshaft. Pistons 1&4 are brought to, say, 15 degrees BTDC - then insert the pin and screw in fully. The crank is then rotated nice and slowly until it *just* contacts the pin - this is TDC.
The pin can be left in place even for the final tightening of the crank pulley bolt . Again, degrease the contact surfaces thoroughly, use a new bolt, and it's another torque + angle affair.
The timing belt tensioner needs setting carefully - with all tools removed, turn the crank by at least two revolutions to 'settle' things and re-check the indicating pointer.
Good on you for replacing the auxiliary belt - this often fails with the debris getting into the timing cover and mangling the timing belt!
Have fun!
Edited by anonymous-user on Tuesday 9th July 13:59
280E said:
African or European? I don't know that!....
The first thing I'd do is bring the pistons somewhere near mid-travel with cyls 1&4 on the upstroke - this allows you to rotate the cams without fear of valves kissing the pistons.
Once you've re-fitted the cams and cover, the cam sprockets need holding in place with a 'special tool' whilst the retaining nuts are tightened. As with the crank sprocket, the cams aren't keyed to their sprockets - relying pureley on clamping friction from the fixing nut. The contact surfaces should therefore be cleaned thoroughly with, say, brake & clutch cleaner before assembly with new nuts. The nuts are done up pretty tight (torque + angle), and there is a risk of breaking the cams if you just rely on the 'horseshoe' setting tool in the far end - hence the sprocket retaining tool. Obviously, the 'horseshoe' needs to be fitted along with the retaining tool.
The slots in the cams are offset from centre, and the 'horseshoe' MUST be fitted so that the slots in the cams lie below the centre line.
The plug for the crank setting pin can be a bit hard to access, and will require a female torx socket if original. The pin doesn't actually 'lock' the crankshaft, but stops up against a machined web on the crankshaft. Pistons 1&4 are brought to, say, 15 degrees BTDC - then insert the pin and screw in fully. The crank is then rotated nice and slowly until it *just* contacts the pin - this is TDC.
The pin can be left in place even for the final tightening of the crank pulley bolt . Again, degrease the contact surfaces thoroughly, use a new bolt, and it's another torque + angle affair.
The timing belt tensioner needs setting carefully - with all tools removed, turn the crank by at least two revolutions to 'settle' things and re-check the indicating pointer.
Good on you for replacing the auxiliary belt - this often fails with the debris getting into the timing cover and mangling the timing belt!
Have fun!
Thanks for the tips, actually although I got new oil seals for the camshafts I was planning not to fit them as it just seems too much of a faff to get the pulleys off and I haven't got the new nuts to refit either so I was hoping they won't leak, maybe a bit of 'goo' around them will help?.The first thing I'd do is bring the pistons somewhere near mid-travel with cyls 1&4 on the upstroke - this allows you to rotate the cams without fear of valves kissing the pistons.
Once you've re-fitted the cams and cover, the cam sprockets need holding in place with a 'special tool' whilst the retaining nuts are tightened. As with the crank sprocket, the cams aren't keyed to their sprockets - relying pureley on clamping friction from the fixing nut. The contact surfaces should therefore be cleaned thoroughly with, say, brake & clutch cleaner before assembly with new nuts. The nuts are done up pretty tight (torque + angle), and there is a risk of breaking the cams if you just rely on the 'horseshoe' setting tool in the far end - hence the sprocket retaining tool. Obviously, the 'horseshoe' needs to be fitted along with the retaining tool.
The slots in the cams are offset from centre, and the 'horseshoe' MUST be fitted so that the slots in the cams lie below the centre line.
The plug for the crank setting pin can be a bit hard to access, and will require a female torx socket if original. The pin doesn't actually 'lock' the crankshaft, but stops up against a machined web on the crankshaft. Pistons 1&4 are brought to, say, 15 degrees BTDC - then insert the pin and screw in fully. The crank is then rotated nice and slowly until it *just* contacts the pin - this is TDC.
The pin can be left in place even for the final tightening of the crank pulley bolt . Again, degrease the contact surfaces thoroughly, use a new bolt, and it's another torque + angle affair.
The timing belt tensioner needs setting carefully - with all tools removed, turn the crank by at least two revolutions to 'settle' things and re-check the indicating pointer.
Good on you for replacing the auxiliary belt - this often fails with the debris getting into the timing cover and mangling the timing belt!
Have fun!
Edited by 280E on Tuesday 9th July 13:59
It's my Son's car and it should have been written off a couple of times by now especially since the cambelt broke whilst driving but DIY'ing this repair is cheaper than replacing it and otherwise it's scrap value only so he wants (me) to do it but I'm trying to convince him to get a new car - he can afford it, he's just being tight.
I was wondering about how to torque up the crankshaft - if the locking pin was up to the force required and you are saying it is, is that right?
As for the auxillary belt, the alternator being noisy was on the to-do list before the cambelt broke and since the aux belt was perished/cracked anyway it was a no-brainer to fit new.
As for the cambelt, it didn't actually break - rather it sheared 13 teeth off where it sits on the crank pulley which actually probably helped limit the damage to exhaust valves only as the cams were held firm and didn't spin any further to take out the intakes?
Ha - I think our sons must be from the same mould
There's a small possibility that one or both cam sprockets has slipped relative to the shaft - you'll find out if you're half a tooth or so out when fitting the new belt!
Yes, the crank timing pin is capable of withstanding the final pulley bolt tightening (40Nm + 145degrees) - the load is all down the axis of the pin. The 1.8 and 2.0 16V engines have a plain pin which locates in a slot in the crank - in this case the pin has to be removed for final tightening and the crank restrained using a big screwdriver in the starter ring gear.
In fairness, the little 16V engine is a pretty good design, and belt failure is usually due to (ahem) extended replacement intervals!
There's a small possibility that one or both cam sprockets has slipped relative to the shaft - you'll find out if you're half a tooth or so out when fitting the new belt!
Yes, the crank timing pin is capable of withstanding the final pulley bolt tightening (40Nm + 145degrees) - the load is all down the axis of the pin. The 1.8 and 2.0 16V engines have a plain pin which locates in a slot in the crank - in this case the pin has to be removed for final tightening and the crank restrained using a big screwdriver in the starter ring gear.
In fairness, the little 16V engine is a pretty good design, and belt failure is usually due to (ahem) extended replacement intervals!
Edited by anonymous-user on Tuesday 9th July 19:32
To update/bring closure, I finished the repair yesterday and everything seems fine.
Due to it breaking (stripping teeth) the cambelt whilst running it bent all the exhaust valves so repair was: head off, change all the valves ('kit' included all 16) and seals, a couple of valve guides needed reaming as the bending had 'scarred' them, exhaust camshaft and one roller/rocker arm needed a little polish as one of the rockers had 'jumped' out and wedged between cam and head, pistons were OK and cleaned up nicely, replaced all the gaskets, new cambelt/waterpump/tensioner & idler pulleys, new alternator bearings and aux belt, oil & filter change and new coolant.
Car ran a bit rough for the first few minutes, I suspect due to hydraulic tappets 'resetting' to the new valves etc. but everything nice and smooth now with no errors showing on OBD, the annoying alternator whine now gone due to the new bearings and we've better compression figures than before, tested at (average) 190 psi whereas a couple of years back we only got 140psi so definitely healthier - hopefully ongoing will continue to be good? but I still don't like the way the belt pulleys aren't keyed.
For the record I used a Loctite 518 equivalent as it was half the price, this; https://www.ebay.co.uk/itm/518-Anaerobic-gasket-se...
Son's pleased as the whole parts bill was only around £250, including buying tools and manual. Plus, due to fluid changes etc. the car is effectively serviced as well so he's quids in - was quoted 'at least £1,000' by a garage, meaning a write-off as the car's not worth that, (belt change alone is £350) and it gave me a project for the last couple of weeks, albeit one I wouldn't have chosen but interesting nonetheless.
Still trying to convince him to get a new car but have the feeling he thinks it is 'new' now that it's repaired, he said he'll run it 'till it breaks again for me to fix it next time...
Due to it breaking (stripping teeth) the cambelt whilst running it bent all the exhaust valves so repair was: head off, change all the valves ('kit' included all 16) and seals, a couple of valve guides needed reaming as the bending had 'scarred' them, exhaust camshaft and one roller/rocker arm needed a little polish as one of the rockers had 'jumped' out and wedged between cam and head, pistons were OK and cleaned up nicely, replaced all the gaskets, new cambelt/waterpump/tensioner & idler pulleys, new alternator bearings and aux belt, oil & filter change and new coolant.
Car ran a bit rough for the first few minutes, I suspect due to hydraulic tappets 'resetting' to the new valves etc. but everything nice and smooth now with no errors showing on OBD, the annoying alternator whine now gone due to the new bearings and we've better compression figures than before, tested at (average) 190 psi whereas a couple of years back we only got 140psi so definitely healthier - hopefully ongoing will continue to be good? but I still don't like the way the belt pulleys aren't keyed.
For the record I used a Loctite 518 equivalent as it was half the price, this; https://www.ebay.co.uk/itm/518-Anaerobic-gasket-se...
Son's pleased as the whole parts bill was only around £250, including buying tools and manual. Plus, due to fluid changes etc. the car is effectively serviced as well so he's quids in - was quoted 'at least £1,000' by a garage, meaning a write-off as the car's not worth that, (belt change alone is £350) and it gave me a project for the last couple of weeks, albeit one I wouldn't have chosen but interesting nonetheless.
Still trying to convince him to get a new car but have the feeling he thinks it is 'new' now that it's repaired, he said he'll run it 'till it breaks again for me to fix it next time...
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