Rebuidling 4.0

[kc15842]

So I'm curious about the decision to rebuild vs. looking at a new engine. Seems like you're really experienced at these type of repairs. It just seems like with several issues stemming from a shoddy maintenance history, a new engine would add piece of mind. How's the rest of the truck? Is it a 4x4? hows the transfer case, etc? Was your son at Ft. "Lost in the Woods?" (Ft. Leonard Wood). I took BCT there. Anyway I'm curious about the repair costs for taking the rebuild route. I'm certainly interested in following along. Best of luck!!

Good questions, the decision to rebuild is basically financial. The local yards out here want between 2 and 2500 for a used motor. Even with a replacement motor I'd be wondering what condition is it really in.
It is a 4x4 automatic and so far the trans seems solid. My soldier's last duty station was Fort Riley in Kansas.
Thanks


So far the cost
Bore .020 over- $240
Piston & rings - $200
replacement rod - $106
Crank grind & bearings - $160
yet to buy
gasket set- going Toyota ~ $240 I think
oil pump - ~ $60
water pump- ~ $90
head bolts ~ $120
Timing chains, guides, tensioners ???
Still working on the valves, so far on bank 1 I think all can be reused. Have not touched bank 2 yet.

 

[waypoint]

Timing chains, guides, tensioners ???

Here's my list, tensioners not included as I'd already bought them:

13506-AD010 Chain $187.22
13521-AD010 Crank Sprocket $20.91
13523-AD010 Exhaust Cam Gear $24.76 (x2)
13507-AD010 Secondary Chain $55.60 (x2)
13559-AD010 Chain Guide Right Lower $27.16
13562-AD010 Chain Guide Upper $16.19 (x2)
13561-AD010 Chain Guide Left $66.95
13530-0P011 Idler Gear $16.99

 

[waypoint]

Here's my list, tensioners not included as I'd already bought them:

13506-AD010 Chain $187.22
13521-AD010 Crank Sprocket $20.91
13523-AD010 Exhaust Cam Gear $24.76 (x2)
13507-AD010 Secondary Chain $55.60 (x2)
13559-AD010 Chain Guide Right Lower $27.16
13562-AD010 Chain Guide Upper $16.19 (x2)
13561-AD010 Chain Guide Left $66.95
13530-0P011 Idler Gear $16.99

Other misc parts:

96761-35031 Water Pipe Gasket $2.96
16326-31020 Water Inlet Gasket $0.93
13550-AD010 TENSIONER ASSY, CHAIN 68.78
13560-AD010 Tensioner $31.88
90311-A0005 Seal $13.06

(there's a 3rd tensioner, but I had already bought it locally during my initial troubleshoot)

 

[kc15842]

The chain and chain components are crazy expensive. The only good news I wont be ready for that purchase for another 2 weeks.

 

[waypoint]

The chain and chain components are crazy expensive. The only good news I wont be ready for that purchase for another 2 weeks.

Melling and Cloyes are reputable aftermarket brands in the domestic market and offer complete kits in the $350 ballpark. The parts are import/Taiwan, and I opted to spend extra for Toyota parts...but it's an option to consider.

 

[kc15842]

Lots of shiny stuff in all kinds of locations. The VVT filter collected a few pieces from getting into the VVT controller and saving the cam caps.

 

[kc15842]

I was hoping to simply hand lap the valves after a very good cleaning but no luck. The intakes (IMO) look good and lapped nicely to the seats. The exhaust valves had too many pits even after lapping. My local shop charges $75 to grind the seats. They'll also grind the valves and then I'll do a final lap.
I haven't soaked the head yet.

 

[kc15842]

This didn't help. My son said he would randomly get a CEL.

 

[waypoint]

Valve job seems like a deep rabbit hole, considering the resulting change in cam lobe clearance and the parts needed to adjust it. I dealt w/ this on my prior '03 Tacoma 4 cylinder, which had hardened shims on top of the buckets and no need to remove the cam to change them. My understanding of the 4.0L is that the entire bucket is replaced to adjust clearance.

I was hoping to simply hand lap the valves after a very good cleaning but no luck. The intakes (IMO) look good and lapped nicely to the seats. The exhaust valves had too many pits even after lapping. My local shop charges $75 to grind the seats. They'll also grind the valves and then I'll do a final lap.
I haven't soaked the head yet.

 

[Captsolo]

How many miles on this 2008? Was it lack of maintenance (oil changes) that caused the failure?

 

[kc15842]

Valve job seems like a deep rabbit hole, considering the resulting change in cam lobe clearance and the parts needed to adjust it. I dealt w/ this on my prior '03 Tacoma 4 cylinder, which had hardened shims on top of the buckets and no need to remove the cam to change them. My understanding of the 4.0L is that the entire bucket is replaced to adjust clearance.

That's fact, I only had to grind the exhaust valves so in theory I'll have more of a challenge with 12 buckets. Believe me that crossed my mind too many times before I pulled the trigger on grind the valves and seats.

 

[kc15842]

How many miles on this 2008? Was it lack of maintenance (oil changes) that caused the failure?

I think lack of maintenance and a belief the truck and motor will take anything you can do to it because its a truck.

 

[kc15842]

Valve job seems like a deep rabbit hole, considering the resulting change in cam lobe clearance and the parts needed to adjust it. I dealt w/ this on my prior '03 Tacoma 4 cylinder, which had hardened shims on top of the buckets and no need to remove the cam to change them. My understanding of the 4.0L is that the entire bucket is replaced to adjust clearance.

The buckets

 

[kc15842]

The valves and seats are lapped and ready for reassembly. Heads are cleaned (less some staining) guides clean. Cleaned out all of the oil passages and polished a couple caps because of the dirty oil. I cleaned the cams and VVT controllers and they seem to work fine.
My plan is to assemble this weekend and hopefully the lifter clearances can be set with the lifters I have. $15 a lifter can get expensive.

 

[kc15842]

New wrist pins and bushings, the shop had to hone to the correct fit.

 

[kc15842]

Odd, the main bearings new and the ones that I pulled from the engine don't have the notch on the upper bearing half. I'll call the shop on Monday, anyone see or use these before? I really don't know if the motor was rebuilt before but I sure don't want to take a chance.

 

[kc15842]

screwed up, can't remember breaking a ring before but I did this time. $49 mistake. 5 in with no problems now its time to wait Tuesday.

 

[kc15842]

Torqued mains and rods just waiting for the replacement ring to finish # 6

 

[waypoint]

screwed up, can't remember breaking a ring before but I did this time. $49 mistake. 5 in with no problems now its time to wait Tuesday.

Were you spiraling them onto the pistons, or using a ring expander?

 

[kc15842]

expander, the upper oil ring must have caught the edge of the ring and didn't sit as I pushed into the cylinder, my fault. The others went fine.