Timing tensioner

[Bob_Fla]

850 T5
Do the gears or timing chain have to be removed to replace the timing chain tensioner block to a Banana?
Is there an existing thread on installation?

[fotoguzzi]

Yes to get the old one out. But it's not very hard to pull the gears and chain off, they are keyed so you won't be able to screw it up.

[yogidozer]

Wouldn't it be cost/effort worthy to replace the chain as long as you have it apart?

[pete roper]

The important thing is to make sure the timing marks on the sprockets are aligned when you pull the entire train off. When aligned the left hand piston will be at TDC compression and it's the only place in the cycle where there isn't pressure on the cam to turn.

Also make sure you don't loose the key for the oil pump as it has a tendency to fall out when the sprockets are removed. It's tiny and very easy to loose.

Pete

[Bob_Fla]

So will I need anything else besides:
- New timing chain
- Banana Tensioner
- Gasket
(- sealer?)

[Chuck in Indiana]

I don't have anything to add from what Pete said except I made a simple u shaped tool with a bolt in the side to hold the tensioner away from the chain when reassembling.
Sealer? No.. but I do use some spray on stuff to make the gasket sticky enough that it doesn't move when installing the cover.

[pete roper]

So will I need anything else besides:
- New timing chain
- Banana Tensioner
- Gasket
(- sealer?)

I'd replace the front crank seal in the timing chest as well because you can bet your bottom dollar that if you don't it will leak on start up.

When I'm installing these tensioner I install the mount without the blade and spring, then the timing chain and sprockets, (When arranging the sprockets in the chain try and make sure the key way for the oil pump sprocket is at the top, it makes it a lot easier to get the key back in.) and the last thing I do is install the blade on the pin of the mount. This can be a bit tricky but I just hook it on and then stretch the spring until the eye of the end of it can be slipped into its slot and then tapped over the pin.

Once the spring is on the tensioner blade can be stretched out until it slips into the case and the rest of its width tapped gently down over the pin. Once the nut and washer are installed, (It's a nylock nut so you just tighten it until the blade is in the correct position relative to the run of the chain.) Make sure that the spring is inside the case and not sitting outboard of one of the bolt bosses for the timing chest cover. If this is overlooked it will leak like a stuck pig when you start it up! Guess how I know that?

[pehayes]

Actually, it is technically possible to remove the original and install the banana with the sprockets and chain in situ.  I have done so on my own SPII.  However, while it ensured that the timing remained accurate and no risk of dropping keys etc., I'm not sure it actually saved me any time or grief.

If you want to try.  First remove the bolts from the existing tensioner.  Not so easy as the hex heads interfere with the crank sprocket teeth.  Tricky to rock the sprocket back and forth while unscrewing the bolt about 1/6th of a turn at a time.  After the bolts are out you can reach in with stout channel-lok pliers and roll up the old tensioner into a coil.  Kind of like the way you used to use a little key to open a sardine can and roll up a tear away section of the can's metal.  Installation is easy if you disassemble the banana and install it in parts.  Replace the hex head bolts with Allen  heads and away we go.  I was guided through this by a well-respected Guzzi mechanic.

Patrick Hayes
Fremont CA

[kfz]

So will I need anything else besides:
- New timing chain
- Banana Tensioner
- Gasket
(- sealer?)

Peg nut spanner tool if you want to reuse the crank sprocket peg nut.  The nut is £10 GBP and tool £20 GBP.

Kev

[Bob_Fla]

Two more questions.

Pete Roper - Will I need to remove the shaft to replace the front Crank Seal?

kfz - Educate me. What is a "Peg Nut". And if I do not use a spanner tool I will need a new peg nut to replace the Tensioner or the Crank Seal?

[kfz]

Two more questions.

Pete Roper - Will I need to remove the shaft to replace the front Crank Seal?

kfz - Educate me. What is a "Peg Nut". And if I do not use a spanner tool I will need a new peg nut to replace the Tensioner or the Crank Seal?

On the end ofthe crank is a funny peg nut.  You can get the correct tool or you smack it off with a chiesel.  If you got for option 2 then you may to replace it.

[Howard R]

A little hint, although not specifically mentioned I'm sure Pete knows this.  When you put the chain/gears back on, leave the oil pump key lying on the bench in the safe place where you put it when you took it off so it wouldn't get lost.  Then turn the shaft until the keyway lines up and put the key back in.  There is even a slot in the end of the pump shaft that is just perfect for a screwdriver, almost like someone planned it that way. 

Re: front shaft seal, it lives in the timing cover so it's easy to change the seal while you have the cover on the bench.

Howard

[larrys]

My Cal 1100 has 32K miles. Is it due for a tensioner?
Larry

[fotoguzzi]

My Cal 1100 has 32K miles. Is it due for a tensioner?
Larry

1100 should have the later rensioner so, no.

[Chuck in Indiana]

I hate dealing with springs, etc. so made a simple clamp to hold the tensioner back while installing the timing chain. Just took a few minutes, and saved a lot of aggravation.
001 by Charles Stottlemyer, on Flickr

[Bill Owens]

1100 should have the later rensioner so, no.

I must say that I'm not quite sure about that Foto. I have checked the tensioner on my hydro motor at about 35000 miles and found that the floppy foot had what I thought was significant wear and more importantly the spring to be what I think is very weak.You may have seen a separate thread about the Valtek tensioner not fitting in a hydro motor because of a casting that is in the way. Something that I observed is that If I take the mounting plate of the Valtek type tensioner and hold it up to where it should be mounted I noticed that the threaded rod looked to be in the same location as the slotted rod is on this later type tensioner when it is installed.
So, I have taken the floppy foot tensioner off, cut the slotted rod off flush , it is brazed to the mounting plate and is something like 7 or 8 mm in diameter.This rod has a flat rivet type head on the other site of the mounting plate. I ground 1 or 2mm off the rivet head, drilled a 5mm hole in the center of it , and brazed a 5mm bolt to it replacing the original slotted rod.  Then I ground a little of  the head of bolt so it will clear casing in the back. Now I believe I may be able to use the Valtek type blade on the stock mounting plate. I am ready to install but am stalled with other duties. I still have to ad some small washers inboard of tensioner foot in order to align with chain, cut 5mm bolt to proper length and install nut. I have one question, the original Valtek rod is not threaded where it passes through the blade and spring eyelet, but mine now does. Should I be concerned about wear from those threads on the spring ?

[Tom H]

While doing my Hydro, there was a tip about first lining up the marks on the sprockets and then take a marker or the like and put a mark on the chain and a corresponding mark on the sprocket. This way you did not have to guess where the sprocket goes in the chain to get the sprocket marks to line up.

At about 25K mile my tensioner was fairly worn , so I replaced it.

Here is the Valtec issue with my at least Hydro. Look at the second picture and you'll see the raised area.:




Tom

[Bill Owens]

Something I forgot to mention, I had telltale wear marks on case from sloppy chain.

[Tom H]

A few more images and the torque spec for the crankshaft nut. Note the spacers under the stock tensioner mount. IIRR the Valtec would not line up on the chain even if I would have used a spacer, not sure about this though?:




roll die


Another tip, to hold the engine so it does not turn while working with the nuts, put a screwdriver or the like though the timing hole in the bell housing.

Tom