Serpentine Belt Tensioner Pulley.. Omg Did I Break It?

skyway · December 12, 2015

Afternoon guys have you ever been doing what seemed like very simple job and it went some what downhill very quickly?

Well that was me today I really hope it hasn't gone as badly as I think it has and someone else has had this happen.

So while trying to fit my new idler pulley I loosened the tensioner bolt however it did not slacken the belt one bit, so in true blundering fashion I kept going a little bit ... giving a small push then a bit more until of course the bolt came out and the pulley went flying, so I'm now in the position of not being able to move my car to someone who could rectify my blunder, I think the tensioner itself is jammed up somehow and i think also to get to it I may have to take out the radiator (mind you could do with a new one anyways).

I really hope someone could tell me that all I need is to tap the car with a magic hammer and all will be well again.

thanks again for reading and for any advice, feel free also to laugh at me as I really think I deserve it :)

Oh also the pulleys have been changed its the belt I cant get back on as well its tighter than a gnats bum.

john

ambermarine · December 12, 2015

Allan

Screw the bolt back in to the tensioner and when you get it in all the way using a breaker bar or extension ease the tensioner back pushing anti clockwise this will relieve the tension on the belt and you can slide the belt out .Take the bolt back out and fit the new pulley then follow the same course to releve the pressure and slide the belt back on let the bar go and the job is done.If you can use the centre of the old pulley in the first operation it will act as a spacer for the bolt.Remember that this is a left hand thread so when you tighten it up it will bring the tensioner right back to the slacken off position do not worry about that when you let it go it will go back up.Make sure the belt is on correctly and the ribs are all in the correct grooves before starting the engine.

skyway · December 12, 2015

MR Abermarine Sir you are a scholar and a gent... I shall run out with my magic hammer right now

skyway · December 12, 2015

Ambermarine as i'm turning it anticlockwise it feels as if its a spring and im rotating it from 3 o'clock to 10 and but it doesn't slacken the belt and im afraid to break something shall i just push it more?

thanks again and sorry for the stooopid questions

ambermarine · December 13, 2015

It is a spring ,without knowing the situ of the belt at the moment it is impossible to say what is the next exercise, could you take a pic of the situation and then we can see whats what.If you are turning it anticlockwise and it is feeling the tension of a spring you need to turn it through that resistance to slacken the belt it will rotate enough for that to happen but you have to use a lot of effort, that is the reason for using a extention bar on your socket.

steve2006 · December 13, 2015

It sounds like you are having the same problem as I did when trying to replace the sepentine belt, they seem to be too small to fit over the pulleys, on one attempt I was actually kneeling on the top of the engine pulling the belt up with both hands trying to get it over the pulley.

With less complicated pulley set ups you can actually wind the belt on but not with these engines.

Most belts are described as follows 6PK**** which translates as a 6 rib belt and the **** is the belt length in mm so a 6PK2228 is a 2228mm length.

The problem I found was there are different belt lengths quoted for the same engine 2228/2241/2250 are all shown to fit the LS400 engines.

After ordering 2 different length belts both being described as suitable and too tight to fit I decided to go one size bigger and found the solution.

The belt was a Gates 6PK2270, this fitted easily over all the pulleys and the auto tensioner was midpoint between fully pushed back and fully slack i.e. where it should be leaving enough adjustment as the belt stretches to take up the slack.

There is very little play in the tensioner maybe 30 degrees on the ratchet from one end to the other.

skyway · December 13, 2015

ok so this morning with a clear head and some sunlight n rain I went out to survey the damage I had caused in my haste.(silly silly boy that I am)

where I foolishly unbolted the tensioner pulley last night and it pinged off with violence it sheared off a piece of metal from the pulley mounting, so i may have to replace that whole thing now .

something i didnt expect is that there was no washer behind any of the pulleys which I found strange, Is this right?

I have bolted it all back together now though and yes in the end the penny dropped on how the tensioner works, not sure i shall ever live this one down.

The tensioner pulley I was of course worried about not sitting right however there isnt a wobble in sight.

thanks for your patience

skyway · December 13, 2015

ok so as I did shear a bit of mettel off the mounting of the tensioner I'm going to replace the unit with this..

http://www.ebay.co.uk/itm/301639567063?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I think its the right one has anyone changed one and if so do i need to take anything out to get to the 4 bolts?

thanks again

ambermarine · December 13, 2015

That is ok for now I am a bit worried that you could have damaged the the screw housing for the bolt that holds the pulley on you may have snapped a piece of it off . If it is only a small end of the thread it should be ok keep an eye on it for a while any excess movement develops replace the tensioner the replacement of tensioner and pulley is the same procedure for removing the belt with the addition of removing the tensioner housing also.

If there were no washers on it when you took the pulley off there won't be provision for them.

cruisermark · December 13, 2015

"It sounds like you are having the same problem as I did when trying to
replace the sepentine belt, they seem to be too small to fit over the
pulleys, on one attempt I was actually kneeling on the top of the engine
pulling the belt up with both hands trying to get it over the pulley."

this made me laugh

i have done the belt on my 400 in the past - took me 15 mins and few attempts

cruisermark · December 13, 2015

there is a video here for the 430

ambermarine · December 13, 2015

Got mixed up on replies ,in answer to the removal of tensioner ;

Make sure the belt is off the tensioner pulley before removing the bolts.

It will probably be a easier install of the new tensioner if you remove the pulley before trying to install the tensioner that way you will be able to put the tensioner bolts in without having to move the pulley out of the way.Remember when you try to undo the pulley bolt it is a left hand thread put the tensioner in a vice or you will struggle to undo the bolt.

ambermarine · December 13, 2015

Having made further research on replacing the tensioner it as become apparent that removal of the alternator is required to get the tensioner off the engine .

This is because the tensioner bracket sits behind the alternator and is held in place by one of the long studs the alternator is mounted to the engine on.

It will become obvious as you get to the area around the alternator .

There is a video tutorial on utube that shows the full replacement of the cambelt on a ls430 and in the tear down of the front of the engine it shows the procedure for the removal of the serpentine belt tensioner.

I respectfully suggest you watch the full video it will help you with the geography of the parts and show you useful procedures that will come in handy later

skyway · December 13, 2015

oh dear it seem as if i really have messed up its not going to be fun doing this on the street in winter.......ohhhhhhhh nooooooo

ambermarine · December 13, 2015

If you have three bolts securing the tensioner to the engine it should hold on ok, it is after all not a moving part ,keep a close eye on it and wait till the summer to repair it.

skyway · December 13, 2015

its connected it the engine ok its the mounting point for the pulley that is not flat anymore well it is a bit but some of it sheared off but i think there is enough on it.

its next to a 5p coin

ambermarine · December 14, 2015

That looks like the edge of the body of the tensioner and is unlikely to cause it to fail.As I suggested yesterday leave it and monitor the situation over the next couple of thousand miles.

I would leave it alone after that if it shows no sign of worsening ,keep the new tensioner which can be fitted when the cambelt is renewed.