Octanejunkie's T4R project - 99 SR5 4WD 5-speed

[JohnMc]

Looks like it has both in your kit. I see 2 rollers listed.

Sent from my SM-A536V using Tapatalk

Correct.

The timing belt has the idler roller on top between the two timing gears, and a tensioner roller on the right/passenger side, and on the left/driver side, it uses the water pump as a roller there.

The two rollers are items #2 and #3 in the kit part listing.

 

[octanejunkie]

There's only an idler and tensioner pulley for the timing belt and both look to be there. Maybe they were missing the ac belt tensioner pulley?

You are correct, I went back to the comments and it was the AC idler pulley mentioned...

Worth replacing now? It's external and "easy" to get to at any point, no?

 

[Bad Luck]

You are correct, I went back to the comments and it was the AC idler pulley mentioned...

Worth replacing now? It's external and "easy" to get to at any point, no?

Sent from my Pixel 4 XL using Tapatalk

I would replace it now, but I personally hate having to replace a part later that I already had access to.

 

[JohnMc]

Give it a spin with no belt on it, see how it sounds. If it's silky smooth and not making 'whirring bearing noises' then you'll have another chance to check it again in another 100K miles. If it makes the slightest bit of noise, replace it.

I use the same logic on the cam and front main seals. If there's the absolute faintest hint that they might have leaked any oil at all, replace them. If they're absolutely bone dry, leave them alone and check again next time.

 

[brillo_76]

I had that AC pulley Tensioner bolt break. Took me 2 weeks a few hours a day to get that out. :/ You make darn sure that pully moves freely on that bracket and that Tensioner bolt is under anti-seize ( at least in the rust belt)

Those pulleys on the AC adjuster bearing you can mostly feel then they start going bad. They are not horrible to change provided everything is moving freely as that collar can get stuck on that pulley bolt too.

 

[octanejunkie]

Give it a spin with no belt on it, see how it sounds. If it's silky smooth and not making 'whirring bearing noises' then you'll have another chance to check it again in another 100K miles. If it makes the slightest bit of noise, replace it.

I use the same logic on the cam and front main seals. If there's the absolute faintest hint that they might have leaked any oil at all, replace them. If they're absolutely bone dry, leave them alone and check again next time.

I suspect NOT replacing the seals is the MO of most home hobbyists and shops looking to save time and make more $ - which means they may not have been changed with the last TB around 50K miles ago (according to the sticker on my core support)

Good advice on the AC tensioner

Sent from my Pixel 4 XL using Tapatalk

 

[octanejunkie]

A buddy of mine suspects the thermostat housing as the culprit

I might just clean up that front corner and see if replacing the thermostat gasket does the trick to stop the leak

My AC squeals when the clutch engages so I ordered an AC idler pulley just to be safe, PN 88440-35060

I also ordered a set of thread chasers, inside and outside, so thread cleaning will be part of the program moving forward - more on why to come.

https://a.co/d/9TDknwv

 

[Romeo1]

Was responding to [MENTION=643801]Romeo1[/MENTION] removal Macgyvering, It's always good to c someone properly re-torquing the bolt.

Yeah. My OCD won't let me rattle it on. I had to use an old stainless steel milk pipe for a cheater on a snap on half inch torque wrench to get the click. That crank bolt was an ass pain to get torqued.

Next time I'm buying a holder. F it....

 

[Romeo1]

Was responding to [MENTION=643801]Romeo1[/MENTION] removal Macgyvering, It's always good to c someone properly re-torquing the bolt.

Edit to add, Zero extra points awarded though.....[emoji2957]

 

[Romeo1]

On the kit I bought, both were there. One on the tensioner and the other one between the cams.

Mine we seeping in the middle and didn't go on to the crankshaft, I had a fun time pulling off the timing gear on the crankshaft to change the front main oil seal. :/ I think there are pictures of that in my build thread somewhere.

Sent from my SM-A536V using Tapatalk

I when bought my kit, it had 2 idlers also.

 

[Romeo1]

A buddy of mine suspects the thermostat housing as the culprit

I might just clean up that front corner and see if replacing the thermostat gasket does the trick to stop the leak

My AC squeals when the clutch engages so I ordered an AC idler pulley just to be safe, PN 88440-35060

I also ordered a set of thread chasers, inside and outside, so thread cleaning will be part of the program moving forward - more on why to come.

https://a.co/d/9TDknwv

The housing is O ring flange from the thermostat if I remember right. Check the hose from the oil cooler also while your in there.

 

[octanejunkie]

Weekend Update: 254,154 miles

Leak is fixed!

I cleaned up the area with degreaser and pressure washing a few times with some liberal brushing in between.

Obviously, still some work to do, but it's 100% better than it was!

Once clean, it was obvious that the source of the leak was actually behind the thermostat housing, the water pump-to-block seal. Before tearing it all apart I decided to check the torque on the thermostat housing bolts and boom, the bottom bolt was not tight, <14# feet.

Re-torqued all 3 bolts and no more leak!

The housing is O ring flange from the thermostat if I remember right. Check the hose from the oil cooler also while your in there.

Yup, the gasket installs on the thermostat and seals the housing , PN 16325-62010. I have one but did not use it, yet. The oil cooler hose was not leaking, I had already validated that.

Well, the good news is I now have all the parts to replace the timing belt and water pump, and I'm no longer in a hurry to do so, but I will keep an eye on the coolant temp and level for the next 50K miles.

Not knowing the exact service history of the truck makes me a bit nervous now, if one bolt wasn't torqued to spec, how many others aren't either?

Not sure if it's worth pulling the covers and pulleys (and radiator and fan) to inspect and torque the water pump, but that would give me better access to do the CS144 alternator swap. That would be a lot easier with the thermostat housing and lower radiator hose out of the way...

 

[brillo_76]

Dang I was correct. Even a blind squirrel finds a nut every once in a while......

Glad it was that simple. Someone didn't torque those bolts and nuts.

I can see the thermostat housing nuts not snug enough if someone changed the thermostat. Things happen..

Sent from my SM-A536V using Tapatalk

 

[Romeo1]

Just do et. Go in and baseline everything. You'll be glad you did. I say just bite the bullet and do it all. Do your valve covers and lash. That will let you replace the cam seals with 4 bolts and zero drama. Roll on your accessory drive parts, your new alternator. With that you won't smell the oil on headers anymore. Your injectors will be done, everything will be solid, and you won't have to look at boxes of parts in the garage anymore.

Now if I could just get my projects done.....lol.

Naw man I get it. It just takes time. Some times, "time" is hard to come by for this sort of work.

 

[habanero]

Nice detective work

 

[octanejunkie]

GM Diode mod

To get more voltage to my AGM battery out of the stock factory alternator I decided to try this mod and it works (to increase charging voltage from the alternator to the battery).

I'm getting 15.39-15.89v at idle off the stock factory alternator.

I had to trim (filed, actually) the diode body to fit in place of the ALT S fuse (mini 7.5) but it's in there.

I ordered this Littelfuse 02400104P 1A Mini Diode Automotive Fuse-4Pack https://a.co/d/9X5xU1D

EDIT - adjusted voltage numbers above

 

[blarchitect]

^^ Why would you risk it? The fuse is a safety feature, a diode is not. Enlighten me if I'm wrong

 

[octanejunkie]

^^ Why would you risk it? The fuse is a safety feature, a diode is not. Enlighten me if I'm wrong

The diode has a 1 amp fusesble rating vs the 7.5amp fuse it replaced

Sent from my Pixel 4 XL using Tapatalk

 

[brillo_76]

Interesting. That a diode 1amp fuse would do that.

Another way to do it is to decrease the alt pulley slightly. This way at idle your pushing charging voltage at idle.

Your running slightly high on the voltage side of things, though. What's the voltage at your cigarette lighter plug?

Granted your not above 16 volts yet.

What the diode is doing is creating a voltage drop in that circuit by Probably of . 7 volts. For those reading and curious. Which is making the alt think the battery is low and pushing out more current to charge it.

Sent from my SM-A536V using Tapatalk

 

[phattyduck]

GM Diode mod

To get more voltage to my AGM battery out of the stock factory alternator I decided to try this mod and it works!

I'm getting 15.69-15.89v at idle off the stock factory alternator.

I really hope that is 14.69-14.89V - otherwise you are hurting your new battery and maybe some of your interior electronics.

Even then, that's a bit high of a charging voltage for AGM...

-Charlie