Rescuing my Volvo after 3 years parked

[jbg]

I managed to get some time in to work on the car between rain and thunderstorms. The hood again was a challenge to unlock, though the PB B'laster did work well on the hood hinges. Small victories!

Prior to getting to the car I went to Harbor Freight and bought one of those digital 1/2" torque adapters. I have not used it, but I did open it and got this pic to see how it would work with the radiator in place.



It does fit but it doesn't leave a lot of room to swing the breaker bar. I could remove the air filter housing but I think removing the radiator is the way to go. Or perhaps remove both the air filter housing and the radiator.

I removed the glow plug relay. I plan to test this at home. Several of the control/signal wires in the 4-pin harness are in really bad shape. The wire insulation deteriorated before my eyes with movement of the harness.





I'll have to dig out the replacement harness and add that to the list of to-do's. Next was to remove the master cylinder. The 4 brake lines and fittings were in very good shape. I have a set of line wrenches and everything came apart easy. I have the master cylinder and brake fluid reservoir in a zip top bag.



The bad news is the 4 crank damper 6mm internal torx bolts seem to be in pretty rough shape. One seems to be physically damaged. Another stripped, and yet another looks like a bit was pounded into it on the flats. Finally the fourth one looks okay?



Taking a picture was awkward but I think this helps. Here's another with a healthy dosing of PB B'laster:



Looking at the above, the bolt at ~11:00 looks like it is stripped out. The bolt at 2:00 looks okay to me. The bolt at 5:00 looks like it is stripped or "modified" on it's flats. Lastly, the bolt at 8:00 looks both stripped and perhaps physically damaged. I think I have my work cut out for me. I soaked it all down in PB B'laster.

I think it's the right move to remove the radiator, based on the HF torque adapter fitment and the condition of the 6mm internal torx bolts. At this point in the day yet another storm was coming and I was running out of time to get to an appointment. I figured I would check to see if the transmission lines into the radiator were removable. The top was very easy, perhaps even a little loose, the bottom was not. The threaded union was not turning, instead the fitting in the radiator was. The line was also moving with the union fitting. With some PB B'laster, an adjustable wrench, and a 15mm line wrench, I was able to get it loose. I think I should be able to pull the radiator next week and get more room for the crank damper bolts.



I have some experience with removing stuck bolts. But each one presents its own challenge. Plus the location of them is an additional challenge. I'm thinking a map gas torch, spray bottle of water, Mayhew screw extractors (and drill), vice grips, and a rich tapestry of swearing, will hopefully get them out. That will likely be next week.

[ngoma]

Photographing those crank damper screws is a difficult scene for autofocus cameras to capture clearly. Yours came out surprisingly good. Still a little indistinct to get a really good idea on the inhex conditions on those screws. Can you shine a flashlight directly into them as you take the next photos? That may give us a better idea of what next steps to take. Hard to imagine someone would reinstall chewed up screws there.

[jbg]

ngoma,

I'll try. I won't be back there until next weekend. Looking at the Green book those screws/bolts should only be torqued at ~15 ft/lbs. Granted I don't know how tight they really are, plus there is likely a bond of rust. I did get a ratchet on the 2:00 bolt and when I "turned" it the engine turned. The bolt felt pretty darn tight. So now I am thinking that at least there is one bolt that is a lot tighter than ~15 ft/lbs! I think my small impact driver could help with that one.

The large crank bolt, is it clamping both the harmonic damper and the crank timing belt gear onto the crank snout? The 4 6mm inhex bolts, they are screwed into the crank timing belt gear and also clamping the harmonic balancer to the crank timing belt gear?

It looks like if I removed the front crank bolt it would give me more room inside the harmonic balancer to work, and fit tools. The Green book says to first remove the 27mm bolt and then the 4 inhex bolts. If I did this would the crank timing belt gear become loose or fall off the crank? Or is there like a woodruff key on the crank snout and the timing gear to keep it all together? I don't want to disturb engine timing as I am not replacing the timing belt yet. I just want get to the 4 inhex bolts removable per preparation. Though replacing the timing belt is something I will do soon.

Here is the small parts list so far:

• Front timing belt
• Water pump o-ring
• Timing belt idler pulley
• Front crankshaft oil seal
• 4 inhex bolts (stainless steel; M8x1.25; 6mm Allen head)
• Raybestos MK1917 brake master cylinder rebuild kit (maybe?)
• Saginaw power steering pump rebuild kit
• Power steering pump bracket bushing (is 1 or 2 needed?)
• Power steering return hose
• Air conditioning, alternator, and power steering/fan belts
• Fan switch (and grommet)

[ngoma]

Originally Posted by jbg

The large crank bolt, is it clamping both the harmonic damper and the crank timing belt gear onto the crank snout? The 4 6mm inhex bolts, they are screwed into the crank timing belt gear and also clamping the harmonic balancer to the crank timing belt gear?

Yes.

Originally Posted by jbg

It looks like if I removed the front crank bolt it would give me more room inside the harmonic balancer to work, and fit tools. The Green book says to first remove the 27mm bolt and then the 4 inhex bolts. If I did this would the crank timing belt gear become loose or fall off the crank? Or is there like a woodruff key on the crank snout and the timing gear to keep it all together? I don't want to disturb engine timing as I am not replacing the timing belt yet. I just want get to the 4 inhex bolts removable per preparation. Though replacing the timing belt is something I will do soon.

I think that's right (been a few years so not entirely sure-- hoping somebody else can double check).
No woodruff key, that's why sufficient torque on that bolt is imperative. Kind of a non-common method and the base cause for what is now probably the #1 reason for the D24 (arguably unfair) poor reputation of self destruction after TB maintenance by mechanics who do things the "normal" way.

The crank cog gear doesn't fall off so easily.

===== Later Edit ======

Not entirely correct. Please see v8volvo's better description below in post #37.

===================

[jbg]

Originally Posted by ngoma

The crank cog gear doesn't fall off so easily.

Thanks. Just trying to get my head around what does what.

The plan for this weekend is to drain the coolant and remove the radiator. Once that is done I'll try and get the inhex bolts cleaned of debris and figure out a plan of attack. I am going to purchase a new 6mm inhex bit like you suggested to give me the best chance of getting a few loose.

[jbg]

I had another thought about this task. If I remove the radiator and the air conditioning condenser, and grille, will I have access to the harmonic balancer through the core support? Ideally, if I can see the bolts and have space for tools I believe I'll be more successful at this process.

The AC doesn't work. My thought was to verify there was no refrigerant in the system using the Schrader valve.

[v8volvo]

Originally Posted by jbg

The large crank bolt, is it clamping both the harmonic damper and the crank timing belt gear onto the crank snout? The 4 6mm inhex bolts, they are screwed into the crank timing belt gear and also clamping the harmonic balancer to the crank timing belt gear?

It looks like if I removed the front crank bolt it would give me more room inside the harmonic balancer to work, and fit tools. The Green book says to first remove the 27mm bolt and then the 4 inhex bolts. If I did this would the crank timing belt gear become loose or fall off the crank? Or is there like a woodruff key on the crank snout and the timing gear to keep it all together? I don't want to disturb engine timing as I am not replacing the timing belt yet. I just want get to the 4 inhex bolts removable per preparation. Though replacing the timing belt is something I will do soon.

Here is the small parts list so far:

• Front timing belt
• Water pump o-ring
• From crankshaft oil seal
• 4 inhex bolts

Originally Posted by ngoma

Yes.


I think that's right (been a few years so not entirely sure-- hoping somebody else can double check).
No woodruff key, that's why sufficient torque on that bolt is imperative. Kind of a non-common method and the base cause for what is now probably the #1 reason for the D24 (arguably unfair) poor reputation of self destruction after TB maintenance by mechanics who do things the "normal" way.

The crank cog gear doesn't fall off so easily.

Well there "kind of" is a woodruff key in there, in the sense that there is a fixed key inside the crankshaft timing gear that aligns the gear with a keyway on the crank snout. The issue of course is that the key does not have anywhere near the strength necessary to perform the task of keeping the running engine in time, hence the reason for the high required torque on the big center bolt. That torque is what keeps it all together for the long term with a running engine, by force and friction alone. The key and keyway are just there to aid assembly. And what's more, they don't fit especially tightly. So anytime you loosen the big center crankshaft bolt with the 27mm head, you risk timing drifting to some degree. But thanks to the keyed installation on the crank, it can't drift more than a relatively small distance.

Here's the setup you are working with.
- The big bolt with 27mm head holds the outer "balancer" tight to the crankshaft.
- The four small bolts with 6mm inhex heads hold the timing gear to the back of the balancer (they thread into the timing gear). So, the crank turns the balancer, which turns the timing gear, which turns the timing belt.

In other words, no, the timing gear is not sandwiched between the balancer and the end of the crank. The timing gear is like a donut and just floats behind the balancer on the outer perimeter of the crank snout, it has no internal flange. The big bolt exerts no force or contact on the timing gear -- only on the balancer.

Thus if you do as you say, jbg, and remove the big central bolt, then no there isn't any risk of the whole sandwich falling apart. But what WILL happen is that the key in the timing gear (which again does not fit very tight in the crank keyway) will be the only thing maintaining engine timing in position. So you'd get some timing drift. And worst case, the entire balancer and gear assembly could work loose from the crankshaft as you tried to work on the inhex bolts.

This is just $0.02 here, but I think if I were in your position, trying/preparing to deal with those mutilated inhex bolts, I would simply not worry about them for now. The good news is that they are in there and seem to be tight so they're not a functional threat, just an obstacle for service. It will be a battle to try to do anything with them in situ, with them on the engine down there in a hard to reach location.... but, you don't have to do anything with them there. Instead my move, whenever the time comes that you want to change the timing belt, would be this:
- Loosen and remove the big center bolt (this is after bringing engine to near TDC, other timing service preliminary steps etc as per greenbook)
- Use tool 5187 per greenbook to bring engine back to TDC with the center bolt removed
- Loosen timing belt using your preferred method
- REMOVE the entire balancer/timing gear assembly from the crankshaft as one combined unit, with the 4 inhex screws still in place and tight.

Now you have the assembly on the workbench where you can easily attack it with impact tools and/or heat.... or, most likely easiest of all, simply use a large drill bit and drill the heads off those bolts. Then separate the two parts, unscrew what remains of the bolts from the timing gear, and replace the hardware with new.

Fun to watch all the progress, cheers!

[ngoma]

Thanks for the corrections. My hazy memory!

[jbg]

Originally Posted by v8volvo

Now you have the assembly on the workbench where you can easily attack it with impact tools and/or heat.... or, most likely easiest of all, simply use a large drill bit and drill the heads off those bolts. Then separate the two parts, unscrew what remains of the bolts from the timing gear, and replace the hardware with new.

Oh my gosh, v8volvo, thank you for that very timely reply! I am literally packing up tools and stuff to head to over to the car. I think my plan will be to remove the balancer and gear today, free up the accessory belt adjusters and remove the belts, etc. I'll get the engine to TDC on cylinder 1 and follow long in the Greenbook.

The goal is to bring back parts and subsystems to work on them in my garage. Your idea is perfect! I want to drive the car out of the holes it is in, in order to get a jack under it and have a look at the brakes. I will return with the parts necessary to replace the timing belt. Hopefully I can get that doing in ~2 weeks.

[jbg]

Originally Posted by v8volvo

- Loosen timing belt using your preferred method

I re-read what you wrote and this caught my eye. The Greenbook says to slacken the water pump bolts to release timing belt tension. What other ways are there?