Gen 2.5: Solid Timing Belt Tensioner?

[BEG]

My hydraulic timing belt tensioner failed on me the other day. After doing about an hour of highway driving at around 75mph, I slowed down to a stop light and heard what sounded like lifter tick but louder. That progressed to all out metal-to-metal clanging at which point I just about crapped my pants thinking I had skipped timing and bent valves. I had the Monty towed home and tore into it to see the damage. To my surprise, the engine was still in time and the belt had not skipped, but the tensioner was limp and the awful clanging was the sound of the tensioner pulley bracket banging against the tensioner body. I ordered a new tensioner and once it comes in I'll button it back up, but it made me think of how awful the Mitsu design is for such a critical component.

I've done plenty of timing belts and most have either a hydraulic or spring-adjusted solid tensioner where the tensioner itself sets the initial belt tension. The 6g74 requires you to set the initial tension and there's all kinds of opportunities for error: Does the eccentric pulley get torqued clockwise or counter clockwise? How do you maintain consistent torque on the eccentric pulley while simultaneously tightening the pulley bolt? How accurate is your measurement of the gap? When it comes to putting the pin back in the tensioner, how easy is "easy?" Aside from human error, there's also the chance of the tensioner leaking and failing without warning.

In my searches for a solution, I happened upon these tensioners for the DOHC 3.5:

They work in conjunction with a replacement non-eccentric pulley:

I understand the benefits of a hydraulic tensioner, but plenty of vehicles use solid tensioners. Even the Mitsu 3.0 V6 has a solid tensioner. A setup like this takes away a lot of the opportunity for error and mechanical failure. I'm planning on using a replacement hydraulic tensioner with an added safety hack from a Volvo, but I'm curious what everyone's thoughts are on using a solid tensioner for an expo vehicle. I'm thinking I might gut my old tensioner for the SOHC and adding a bolt and locknut as a replacement in case this new one fails.

TL;DR: Aftermarket solid tensioner with manual adjustment vs. complicated OEM hydraulic auto-tensioner?

 

[MummifiedCircuitry]

I'd never thought of that for monteros, but that seems like a good idea. I know this is belt, not chain, but I used to always switch to manual timing chain tensioners like that on my motorcycles. The OEM ones were sort of crap and let the chain have too much slack and you can actually hear them slap when you put load on them. I think you should try it out and just keep an eye on any wear, otherwise you should have much better peace of mind with a solid system. Can you elaborate on the parts you plan on using from a volvo?

 

[BEG]

...I used to always switch to manual timing chain tensioners like that on my motorcycles...

Same here. That's why I started researching it in the first place but the DSM guys beat me to it.

Can you elaborate on the parts you plan on using from a volvo?

Not so much parts plural, just one part. I'm pretty familiar with Volvos (still daily drive a 245) and the engines that use a hydraulic tensioner have a nylon safety shim that snaps onto the piston:

The shim keeps the piston from fully collapsing into the tensioner in case of a failure or if parked for a long time. I'll file it to fit the gap I want, snap it onto the piston, torque the eccentric pulley and pull the pin. The hydraulic tensioner would then be free to apply more tension to the belt as it stretches but never less. If I ever park it in such a way that the passenger side cam springs pull that side of the belt taut and compress the piston, I don't have to worry about jumping a tooth when I start the car.

 

[midwestracer]

whats the part and where can i get one this is a great topic to bring back up

 

[PA_JERO]

I think the solid tensioner has its good and bad qualities. Yes, reliability is great going to a solid one, but, you will have to go into the motor and manually adjust this every 10k miles or so. Otherwise, what's the point. Most common hydraulic tensioner failures occur from people using cheap aftermarket tensioners. You get what you pay for really. Don't cheap out on these parts and change these parts when it is recommended to change and this problem will become much less of a chance. I think the Volvo part is a great idea. One of those safety stop deals on a OEM tensioner would work great.