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Problem Timing Chain

Marco93

Enthusiast
Messages
68
Location
Udine (NE Italy)
#1
Hi,
My name is Marco, I'm 24 y.o and I'm writing from Italy.
I have a "big" problem with the timing chain of my car.( Renault r4 850cc 1977)
I tried to change It, but maybe I made something wrong.
I Changed the two "pinions" and the chain but trying to check the mark I realized that only after 64 turn of the flywheel the marks returns on the correct position. Is it right?
I'm not an expert, so if you can help me.
Thank you very much,
Regards,
Marco
P_20170825_092636.jpg
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P_20170825_092654.jpg
P_20170825_092715.jpg
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After 4 turns of the flywheel P_20170825_092852.jpg
P_20170825_092847.jpg
 

Attachments

SJC400

Enthusiast
Messages
134
Location
Swindon, Wiltshire
#3
Hi Marco, Firstly I would put the tensioner in position and check it again, If the timing marks on the gears (pinions) don't line up after 2 turns of the flywheel, It could well be the wrong chain?
Count the links in the old and the new chain, just to double check. Try that!
Sure other people on here will have more ideas, but that's where I would start.
Steve
 

Marco93

Enthusiast
Messages
68
Location
Udine (NE Italy)
#4
Hi Steve,
Chain, pignons, are the same as the original.
The chain is made by 64 pieces, maybe is normal that the engine has to turn 64 times to return to the original position?
 

John M

Enthusiast
Messages
84
Location
Yorkshire
#5
Hi Marco,
The length of the chain will affect where the links are on the sprockets as the engine turns. You do not have to worry about this. What is important is that the sprockets are correctly lined up with each other. I assume you locked the sprockets in place before changing the chain. If not then you will have to check your cam shaft is in the correct position relative to the crank shaft.
If your chain was very very long say 150 links then it would take 150 revolutions for the chain to return to the start point.
 

SJC400

Enthusiast
Messages
134
Location
Swindon, Wiltshire
#6
The timing marks should line up with every second turn of the engine. The mark on the chain, would only line up every 64 turns, is that what you mean?
The mark on the chain is not relevant after initial timing is set, as long as the pulley marks line up as originally set, every second turn, that is correct!
 

SJC400

Enthusiast
Messages
134
Location
Swindon, Wiltshire
#7
(By pulley marks I mean gears/pinions, as you call them) As a qualified technician of 40 years, I've never had any issues, as long as these gear/pinion marks are aligned, every 2 turns of the fly wheel (Crank-shaft)
 

Marco93

Enthusiast
Messages
68
Location
Udine (NE Italy)
#8
The timing marks should line up with every second turn of the engine. The mark on the chain, would only line up every 64 turns, is that what you mean? Yes.
The mark on the chain is not relevant after initial timing is set, as long as the pulley marks line up as originally set, every second turn, that is correct!
Ok, perfect. Thank you!!
 
Messages
183
Location
FIN
#9
Hi,

I am also checking my timming gears for my R4_845cc from 1977
I did have the motor repaired 2010 but actually got it running nicely and finally not starting at all, i have checked all items many times.
I did leave old sprockets on place but only put a new chain(without checking its length or chain pieces amounts).
I am wondering and was the tightness of the chain tensioner, if i tightened all bolts correctly there was no movement of the shoe at all, if i loosened a little bit one bolt i could move the shoe.
- shall there be a paper seal under between the tensioner body and the motor flange or not?

this was the situation once upon 2010;

845 jakopää mallia 1975.jpg

how ever now i took some new photos with a straight lever to see that everything would match (i guess i now had the smaller sprocket on wrong position because there is not to be seen the small point )?
R4 timming gears 2.4.2019jpg.jpg
maybe some of you have never seen a rings panner made in USSR, it seem to come in our house in seventies with original LADA tools. flywheel set up when timming matches.jpg
seem to be little off side?

i've checked that piston no1 is on it's TDC.

any suggestions?
 

mojobaby

Enthusiast
Messages
1,170
#10
Hi Orsome, when number 1 piston is at TDC the marks on the crank sprocket and the cam sprocket should line up like this:
Also there is no paper gasket under that tensioner plate

DSCF6584.JPG DSCF6586.JPG
 

JdeW

Enthusiast
Messages
430
Location
Laarbeek The Netherlands
#11
Hi Orsome, when number 1 piston is at TDC the marks on the crank sprocket and the cam sprocket should line up like this:
Mojo, sometimes I wear my pair of glasses (thanks to the garage fairy ;)) but I hope there's no hairline fracture in that chain link..:o
DSCF6586.JPG
 

mojobaby

Enthusiast
Messages
1,170
#12
Oh my Goodness! I hope not. Don't some chains have timing marks?

It was such a long time ago that I can't remember. I'm sure that if I put a blob of paint on that particular link it would have been for a good reason.
 

JdeW

Enthusiast
Messages
430
Location
Laarbeek The Netherlands
#15
Oh my Goodness! I hope not. Don't some chains have timing marks?

It was such a long time ago that I can't remember. I'm sure that if I put a blob of paint on that particular link it would have been for a good reason.
Well the timing is set by the sprockets correctly aligned, flywheel correct mounted with timing mark set (cylinder 1 TDC) and distributor correct mounted only. The chain has nothing to do with setting the timing it just functions as a link between crank and camshaft sprockets. The sprockets have to be the right type, the chain lenght doesn't matter as long as it fits in it's housing and kept on tension.
And sorry I couldn't help noticing what looks like a hair line fracture. Maybe I'll change my pair of glasses for a more blur type :D
 
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