Currently doing the timing belt on my LX. Previous person in there stripped the bolt for the timing belt tensioner. Can I drill/tap/helicoil?

[Obioban]

Specifically my concern is, what's behind that cover? If I drill/tap, will I be dropping metal shavings into the engine oil/somewhere bad? What’s back there?

This bolt:

Also, looking at the picture above after I posted it-- is something wrong with my crank position sensor? Feels weird that it's not centered in that hole...

Thanks!

 

[Patassa]

Specifically my concern is, what's behind that cover? If I drill/tap, will I be dropping metal shavings into the engine oil/somewhere bad? What’s back there?

This bolt:

View attachment 4018243

Also, looking at the picture above after I posted it-- is something wrong with my crank position sensor? Feels weird that it's not centered in that hole...

Thanks!

Yep, easy fix but you have to wait to get the kit. Here you go.

P

Post in thread 'Cross Threaded Timing Belt Tensioner Bolt'

Mar 29, 2025

Alright, I did the repair tonight. It went exceedingly well.
I drained the oil and coolant. Removed fan, shroud, and radiator. Then I removed the crank pully and the timing belt cover down there, didn't have to remove any other components or covers thankfully. Remove the tensioner and pully bolt and then you can kinda wiggle the tensioner pulley out of it's slot and get to the pulley bolt hole.
You want the standard M10 x 1.25 kit here,

++ TIME-SERT Metric Kits ++ thread repair kits and inserts repair stripped threads damaged threads repaired threads threaded inserts for metal thread inserts for metal aluminum inserts threaded inserts for aluminum

stripped out threads, damaged threads, blown out sparkplugs, stripped thread, stripped out theads, helicoils, ford sparkplug repair, repair ford sparkplugs blew out with time-sert, thread repair problems, spark plug ford blown, blew out ford sparkplug, stripped theads, threads stripped out...

www.timesert.com

Once the pulley is out of the way, you can just zip tie the timing belt to get clearance to the hole...

• Patassa

• 
• 

 

[2001LC]

Must difficult:
Best is replace oil pump. But a very big job. Both oil pans must be removed.

Easiest:
You can do in situ, but there are two risk:

1. Dropping metal shavings into crankcase/oil pan, as you drill.
2. Fails to hold long term. Not good! If VVTi will destroy the engine if T-belt then slips. Non VVt, likely just disable vehicle. But, may damage oil pump, water pump and or T-belt covers.

I found one earlier this year cross threads. It was on a VVti 4.7L 2uz. In searching mud at the time. I found a case was non VVTi, done in situ. The time cert fail about two years later. Luckily a non VVt

The key to a good time-cert is a perfectly perpendicular (square to surface plane) holes.
The best and strongest time-sert. The insert come in from back side. These can't come out. I do from back side, on wheel hub rotor bolts. Very strong hold, that does not fail.

In non VVTi I may do in-situ. I would pull radiator to give extra room. Which would help me line up drill bits. I drill very slowly low RPM. With a ton of thick grease on the bit, to catch & hold metal shavings. Removing, cleaning and re-greasing drill bit often. I super clean and use red threads sealer to permanently lock in threads of in-sert to oil pump housing.

I not run bit in, to far. Just enough to get through oil pump housing. We'd not likely do damage to cast iron block, if drill bit run in to far.

Tensioner bolt capture thread (circled), open to crankcase in back of oil pump.

Oil pump O-ring circled, which is at top of oil pump.

 

[excessive]

i 2nd replacing the oil pump (unless you're dumping the vehicle at auction soon or something ) it's a difficult job, but its the only way to fix this correctly. that passage leads right into the oil passage, and there's no way to fix the threads without getting chaff into the oil pump

 

[Obioban]

@2001LC @excessive
Are we just talking drop sub oil pan, drop oil pan, replace pump assembly? Or are there parts that have to come off to drop the pans?
Anything else worth doing while I have the pans off?
Any seals I should be replacing in the oil pump area that don't come with it?

Dumb question, but... are there oil pan gaskets? Not seeing any on the diagrams, but maybe I'm on the wrong diagram?

Is there a gasket between the oil pump assembly (as in, this front assembly that's the root of my issue) and the block? Not seeing that, either...

Thanks for all the help! For sure headed down the route of do it right, do it once, just trying to make sure I get all the parts to actually do it right...

 

[2001LC]

i 2nd replacing the oil pump (unless you're dumping the vehicle at auction soon or something ) it's a difficult job, but its the only way to fix this correctly. that passage leads right into the oil passage, and there's no way to fix the threads without getting chaff into the oil pump

As one can tell, by my post above and post on spark plug blow-outs. I'm not big on time-sert thread correcting anywhere contamination matters.

But my biggest concern, is with alignment. Along with firmly and permanently seating time -sert or Helicoil. There are other types, I've not used. Some may not need drilling out of old, IDK! If one use a drill holder guiding bit squarely., That would be a big plus.

@2001LC @excessive
Are we just talking drop sub oil pan, drop oil pan, replace pump assembly? Or are there parts that have to come off to drop the pans?
Anything else worth doing while I have the pans off?
Any seals I should be replacing in the oil pump area that don't come with it?

Dumb question, but... are there oil pan gaskets? Not seeing any on the diagrams, but maybe I'm on the wrong diagram?

Is there a gasket between the oil pump assembly (as in, this front assembly that's the root of my issue) and the block? Not seeing that, either...

Thanks for all the help! For sure headed down the route of do it right, do it once, just trying to make sure I get all the parts to actually do it right...

Removing oil pump:

4.7L has two oil pans A lower and upper. They both need to be removed, to get to oil pick up tube. Oil pick up tube, is attached to oil pump. Also, Timing belt must be off. Both pans are FIPG 103 oil sealed in place (no gasket).

You need a tube of Toyota 103 OIL FIPG, oil pick tube gasket and O-ring for oil pump. Also oil pump if replacing, which is good idea.
Small figure 8 O-ring, and large O-ring. They're for oil filter bracket and housing.
Coolant & oil.

Some do from below working with engine in situ. I've just pull the engine.

Which is good time to replace engine mounts and R&R any cracked exhaust manifold. I leave transmission in. So one can also get to rear main and oil galley O-ring easy, if leaking.

 

[Obioban]

Alright, parts order is in. Thanks!

 

[Obioban]

So, to avoid pulling the engine or dropping the front subframe/diff...

thoughts on disconnecting the front engine mounts and using my engine support or hoist to lift the engine up a couple inches? Goal being to create enough clearance to remove the top oil pan, while minimizing unnecessary effort...

 

[excessive]

this job can be done with the engine in the truck, as evidenced by this youtube video

I have done this job myself, because the alternator bolt was stripped on my oil pump in my 98 LC. I opted to pull the engine, so I could take care of several other big jobs at the same time ( timing belt, exhaust manifolds, rear main seal ) it's really not that bad to pull the engine on a 100 series. I've done it on 2 different trucks over the years, and did it in my garage with no lift and just a harbor freight engine hoist. Just really take your time, find another car to drive while you can work on it slowly over several days/ weeks.

 

[2001LC]

Many have pulled oil pans with engine in. I've not. To-date, I've just pull engine(s).

I've an engine hoist, two stands and garage. So i just pulled engine. But I've even used tackle & block pulley system, hung from a tree.

I like leaving hood on. By just releasing hood lifts. I use a rope to hold hood up. I pulled rope through a pulley, in case I need to roll vehicle back for clearance. But never have needed to move vehicle. I just roll hoist, to one side as needed. As I only have 18" (best case, stock bumpers) in front of vehicle to work.

The FSM states remove with transmission (A/T) attached. But then I'd need to pull A/T off to place engine on stand. I'd also need more room in shop, for A/T and clearance pulling out/in from/to engine bay. So I just leave A/T in place. It can be a fight, aligning engine to A/T that last 2", especially working alone. But doable. Just don't use bellhousing bolts to pull together. Or you can break bellhousing ears. The trick, is to make sure pilot bush clean and oiled. Also torque convert seated all the way into A/T. It tends, to be stuck out a few inches. Then get alignment correct. Jack under bell housing helps, by using to raised and lower A/T. This aids alignment. As engine mounts touches its frame mounting points. Use hoist to get engine angle correct, and carrying most of the weight. Just gliding over mounts.

I've done it radiator out and AC compressor, still attached to engine. To much work!
I've also done with radiator an AC compress left in the engine bay lines connected. A bit tight, but less work/time this way.

Any seal or gasket not disturb and not leaking, I don't touch.

 

[jsloden]

So, to avoid pulling the engine or dropping the front subframe/diff...

thoughts on disconnecting the front engine mounts and using my engine support or hoist to lift the engine up a couple inches? Goal being to create enough clearance to remove the top oil pan, while minimizing unnecessary effort...

You won't have enough clearance just doing that you either have to drop the front end or take the engine out.

 

[excessive]

I leave the AT attached, too hard to get it re-attached in the engine bay. I disconnect the AC and leave it in the engine bay so no need to re-charge. there is enough room, just barely

 

[Obioban]

I figure it it's coming out, I'll do the rear main seal, so might as well leave the trans behind...

 

[Obioban]

So, how do people handle this...
I'm pulling the engine, as above.
I can't put the timing belt on, because the tensioner mount bolt is striped, as noted above.
To pull the engine, I need to undo the torque converter bolts, to seperate the motor from the trans.
To undo the torque converter bolts, I need to be able to turn the engine over, to access them.
with no timing belt on, I can't turn the engine over.

Anyway have a good strategy for this?

... does it show this is the first automatic transmission I've ever owned?

 

[excessive]

I would highly recommend leaving the trans attached. Take the transfer case off instead.

 

[Obioban]

I would highly recommend leaving the trans attached. Take the transfer case off instead.

because of this or some other reason? I was going to take this chance to do the rear main seal, and mounting it to the engine stand requires the trans to be off...

 

[2001LC]

06-07 VVTi engine, do not turn crank/engine belt off.

Remove spark plugs, reduces resistance on crank (no compression). Put T-belt on. The tension bolt can be jamb in and tensioner installed. The side force on bolt, will be lateral. Like that of nail in a wall, holding a picture. Get a helper to watch and remove TC bolts, as you turns crank and watch t-belt.

JB wield or epoxy may help hold bolt, if needed. Even a thin cooper or aluminum wire laid in port before threading in bolt could help jamb, if needed. Just needs to hold, while gently turning crank.

If just can't get bolt to hold. EDIT 11/8/25: There's no safety position I can find in FSM, for cams. Where crank can be turned, with belt off. FSM just has crank at 45 degrees BTDC. Which is a crank stationary position, where valves will not hit if cams turned.

With spark plugs out and turning crank smooth steady and slowly. Stop at the slightest resistance, with belt on. If belt miss timed. Resistance is interference.

 

[2001LC]

I edited above post: "There's no safety position I can find in FSM, for cams of VVTi engine. Where crank can be turned, with belt off."

I've good reason to believe it can be done in NON VVTi. But just as good reason to believe, it can NOT on VVti. Namely, documented cases in mud.

So safest, is get that tensioner pulley bolt to hold pulley well enough. I know when I found a cross thread tensioner bolt. I was able to sung in, well enough to hold pulley on.

If for some reason, I could not get tension pulley bolt to hold well enough. I would:
1) Pull pans in situ.
OR
2) Install time-sert in-situ. If any concern(s) once install. I'd then install tensioner & belt. Then turn crank to pull engine.

 

[Patassa]

Do whatever you want but a few things

1. If you do the time sert from the front, the hole doesn't need to be deep enough to go all the way through the housing, so it's not like you're just punching through and pushing the aluminum pieces into the sump
2. You're mainly drilling out the old threads, it's not very much material at all and the drill bit will push most of the material outwards. Not inwards. You can also vacuum in the hole if you see any pieces in there.
3. We are talking tiny, almost dust size pieces of aluminum, not big flakes or chunks. So even if you're not 100% clean, is that really going to cause a problem?

 

[2001LC]

Last one I found cross threaded. Was in a VVT engine. When weighing options. I turned to the forum for cases of in-situ. First case I found of time sert in-situ. Poster stated: It had failed, 2 years after install. Non VVT damage is likely, limited to front of engine. VVTi, it will result in interference and likely trash the engine.

Non VVT, I may take the shot. VVt, I don't recommend in-situ.