Timing Belt replacement

[lotusguy]

MikeyRide said:

That makes perfect sense. Never having had to do it, I was thinking you could access the crank from the top of the engine.

Not without the arms of a Gorilla... Happy Motoring! Jim'85TE

>> Edited by lotusguy on Wednesday 20th August 15:35

[Robert87hci]

I agree with everything Jim say's to replace the belt except for removing the alternator. Yes, the adjusting holder must be removed, however when I did mine, I did not need to remove the alternator on my '87. To drain the coolant, I broke open one of the small coolant hoses going to the heater core in front of the motor.
There are two holes in the left and right side exposing the flywheel. I inserted a screwdriver in the hole locking the flywheel from moving when I removed the crank pulley bolt not to mess up my timing marks.
My book says the bolt should be torqued at 63 footpounds. Torque any 8mm bolts no more than 16 to 18 ftlbs.

[lotusguy]

Robert87hci said:

I agree with everything Jim say's to replace the belt except for removing the alternator. Yes, the adjusting holder must be removed, however when I did mine, I did not need to remove the alternator on my '87. To drain the coolant, I broke open one of the small coolant hoses going to the heater core in front of the motor. There are two holes in the left and right side exposing the flywheel. I inserted a screwdriver in the hole locking the flywheel from moving when I removed the crank pulley bolt not to mess up my timing marks. My book says the bolt should be torqued at 63 footpounds. Torque any 8mm bolts no more than 16 to 18 ftlbs.

Robert,

I agree that the alternator does not have to come off (I did my last few belts with it still on), but, it gives so much more working room for so little extra effort, that I always suggest it to those who are doing the belt for the first couple times.

Since you should NEVER exert any pressure whatsoever on either the carbs (early cars), the throttle bodies (later cars), or plenums, due to the possibility of disturbing the 'O' ring soft mount seals to the intake manifold, or bending or shearing off a mounting stud, removing the alternator just makes it a little easier to work around on the front, top of the engine.

Once one becomes experienced in doing timing belt work, they'll figure out that they can skip this step. Happy Motoring! Jim'85TE

>> Edited by lotusguy on Thursday 21st August 07:03

>> Edited by lotusguy on Thursday 21st August 07:05

[Robert87hci]

I found that pulling the belt tight across both cams, a piece of paper towel across the belt {where zip tie comes in contact} and a couple of zip ties will keep it in place on the cams. The towel prevents the teeth from the zip tie hurting the belt, and the rest is done from below without the belt slipping on the cams whilst pulling it tight.
I have done timing belts on almost every make of car under the sun as a professional tech. I would like to say for those whom have never changed a timing belt or do not have the knowledge, this could prove to be a VERY expensive mistake as these are interferance motors, meaning the pistons will crush the valves. You only get one chance to get it right the FIRST time. There are no "do overs" if you get it wrong!
Just my 2 pence,
Robert

>> Edited by Robert87hci on Friday 22 August 02:35

[cnh1990]

Some people have put their body weight or leaned on the carbs and deformed the seals in the cramped quarters of the engine compartment.
Calvin

[Dr.Hess]

Yeah, be careful with them seals. I lost a TC engine to one of those because the worthless shop that rebuilt the motor screwed up the assembly and had one of the O rings drooping down. At 120 MPH #3 leaned out and that was all she wrote. Thus started my experience with doing all my own work. Still have that piston.

Dr.Hess

[LOTUSUSA1]

If one were to service the vehicle on jsck Stands, how high would you have to lift her? I get nervous when she is more than a FOOT above the ground.

[cnh1990]

I use the lowest or 2nd to the lowest setting on my jack stands. I use it on the discs with the wheels off.

Although since Dave Cammack has a lift I just go there now for little things.

Calvin

[lotusguy]

Robert87hci said:

lotusguy said: [quote=Robert87hci]I agree with everything Jim say's to replace the belt except for removing the alternator. Yes, the adjusting holder must be removed, however when I did mine, I did not need to remove the alternator on my '87. To drain the coolant, I broke open one of the small coolant hoses going to the heater core in front of the motor. There are two holes in the left and right side exposing the flywheel. I inserted a screwdriver in the hole locking the flywheel from moving when I removed the crank pulley bolt not to mess up my timing marks. My book says the bolt should be torqued at 63 footpounds. Torque any 8mm bolts no more than 16 to 18 ftlbs. Robert, Since you should NEVER exert any pressure whatsoever on either the carbs (early cars), the throttle bodies (later cars), or plenums, due to the possibility of disturbing the 'O' ring soft mount seals to the intake manifold, or bending or shearing off a mounting stud, removing the alternator just makes it a little easier to work around on the front, top of the engine. >>> Jim, I fail to understand this comment... unless people should "pry" against these items. Please fill me in on what you are talking about. Cheers, Robert

Robert,

As others have already stated, the carb'd models use a thick rubber 'O' ring to combat engine vibration which could cause the fuel in the float bowls to foam up and also to allow the floats to operate unhindered. These 'O' rings also provide a seal between the carbs and the intake manifold. They are not drawn up especially tight (in fact you need to measure and leave a gap of 3/16" between the Intake runners and the carb spacers) and the seal they provide is easily upset, especially once the 'O' rings have hardened slightly due to age/heat cycling.

Also, and this includes the EFI cars w/ throttle bodies, the mounting studs are not particularly robust, and should one put their weight on the plenum or such, they would risk either breaking or stripping these.

When I was first learning about this engine, those who taught me were very insistent about never placing any weight on this area when working on the front of the engine from above. Instead, one should try to place their weight on the cam covers. Hope this clarifies. Happy Motoring! Jim'85TE

[Robert87hci]

Thanks guys for the carbi info, now it's much clearer what you are talking about. My Lotus is the first I've ever worked on and it's fuel injected.
Hey Calvin, I placed 3rd at LOG 23 with Blackie!!!
It was a good time and I was sad not to see you there getting in on the fun... perhaps next year in Alabama.
Cheers,
Robert