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L18 8.1L swap resource thread

Larry - Do you know if the power steering pulley is different between the medium duty and truck Saginaw power steering pumps? I think that is the last piece to my puzzle at the moment.
 
Larry - Do you know if the power steering pulley is different between the medium duty and truck Saginaw power steering pumps? I think that is the last piece to my puzzle at the moment.
Yep, the ZF pump has a .5 mm smaller diameter shaft vs. the Saginaw pumps. You’ll need any ole GM V6 or V8 serpentine belt pulley. I think the pulleys on my K10 and Burb are old TBI 350 pulleys like the one below.

Dorman 300-200

300-200-007.JPG


WOW! the image is bigger than the actual part :yikes:

300-200-001.JPG
 
@Larry

Do you know what the part number is for the water pump bolts? The truck water pump had one bolt which is longer than the other three while the medium duty pump uses the same length bolt for all four holes. Also, do you know if the alternator bracket bolts are the same as the original truck bracket? It appears that the bolts pass through the bracket, the alternator and straight into the head. If they are different, do you have the part number for them as well? The final part I need to track down is the A/C delete idler part number.

I ordered up a bunch of plugs and caps so I can seal the engine up then media blast it to prep it for paint. I got most of the grease scraped off it yesterday, but there is a bunch of rust around the exhaust ports and in the bellhousing area that needs some more attention. I'm thinking about painting the block, heads, coolant crossover, water pump and valve covers hugger orange to kind of match the Chevelle's original engine. I'll leave the timing cover, intake and oil pan in the natural aluminum finish. I've got some stainless ceramic coated headers to put on it. I'll keep the accessory brackets black and will also paint the fuel rails black as well. I think it should be a decent looking engine!
 
I'm thinking about painting the block, heads, coolant crossover, water pump and valve covers hugger orange to kind of match the Chevelle's original engine. I'll leave the timing cover, intake and oil pan in the natural aluminum finish. I've got some stainless ceramic coated headers to put on it. I'll keep the accessory brackets black and will also paint the fuel rails black as well. I think it should be a decent looking engine!
Like this?

401e651a-d9e8-4bac-94f2-83f1c0098bf1-jpeg.315817
 
@Larry

Do you know what the part number is for the water pump bolts? The truck water pump had one bolt which is longer than the other three while the medium duty pump uses the same length bolt for all four holes. Also, do you know if the alternator bracket bolts are the same as the original truck bracket? It appears that the bolts pass through the bracket, the alternator and straight into the head. If they are different, do you have the part number for them as well? The final part I need to track down is the A/C delete idler part number.

I ordered up a bunch of plugs and caps so I can seal the engine up then media blast it to prep it for paint. I got most of the grease scraped off it yesterday, but there is a bunch of rust around the exhaust ports and in the bellhousing area that needs some more attention. I'm thinking about painting the block, heads, coolant crossover, water pump and valve covers hugger orange to kind of match the Chevelle's original engine. I'll leave the timing cover, intake and oil pan in the natural aluminum finish. I've got some stainless ceramic coated headers to put on it. I'll keep the accessory brackets black and will also paint the fuel rails black as well. I think it should be a decent looking engine!

Correct, the bolts for the alternator are 10 miles long and go through the alt straight into the head and are not the same as pickup truck bolts that I know of.

Try these….

12552096 x4 - BOLT, Engine Coolant Pump (3/8-16 X 2 1/8)

11516367 x3 - A/C – P/S bracket bolts

12555610 x1 - A/C – P/S bracket stud

12580771 or 1258774 – Not sure which of these is the idler for A/C delete. You probably need both anyway.

You can find most of these part numbers here and search by a 2002 G-van with a 8.1 or a 2002 3500-HD (GMT400 truck) with an 8.1
 
Took me a couple days to remember to take a pic with the rest of the tasks goin but here's the plug that came for my knock sensors @Larry @bigblock72

View attachment 281653

Yep, they gave you the wrong connector for the knock part numbers in this thread, or mislabed that truck of harness. Are you sure that is the knock sensor? Either you have to research what knock sensors fit that and hope they thread in the block, call them and tell them you need the round Knock sensor connector and they send it to you or cut them off and add a pair of PT308 connectors to match the 213-2829 (Pass) and 213-298 (Drivers) knock sensors, which is what I would do as I always felt their knock sensor leads were too short anyway. I routed the knock sensor wires over the front of the block on the Suburban to keep them out of the heat of the exhaust manifolds. On the K10, they route on the back side of the engine where they make me nervous how close to the exhaust manifolds they run.

PT308
PT308_Primary.jpg

My harness showed up today and wouldn't you know it this is what my knock sensor connectors look like. Even stranger Howells tied 2 different style connectors to one of the leads and they appear to be the wrong ones also. I will call Howells on Monday and have them make some short pigtail adapters like they did for my L29 O2 sensors.

20191228_143205.jpg
 
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I ended up shipping the harness back to have the o2 circuits rewired. Apparently there's an "old" and "new" way they wire them and somehow mine were half and half causing no communication between them and the ecu. It seems much better now I will note that the o2s are more sensitive than I thought they'd be. A slight leak at the 3 bolt collector (bungs in the collector) caused more issues but a v band and reworking the exhaust should fix that soon.
 
My harness showed up today and wouldn't you know it this is what my knock sensor connectors look like. Even stranger Howells tied 2 different style connectors to one of the leads and they appear to be the wrong ones also. I will call Howells on Monday and have them make some short pigtail adapters like they did for my L29 O2 sensors.

View attachment 323704
Same, they'll send you the correct ones for the L18 8.1L mine were Ls style
 
11609264

BOLT,INT MANIF(BLACK)(M6X1.0X72,20 THD)(08.900)(USED ON VEHICLES WITH INTAKE GASKETS CONTAINING SNOUTS).
 
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Here are a few bulletins and Prelim’s from back in the day that will better shed some light on the different intake bolts and gaskets. I should have added these to this thread a long time ago. I’ll go back and add these to the beginning of the thread too


02-06-01-035 High Oil Consumption: October 2002
49313037521_539a140370_z.jpg


49312538058_ed867719a4_z.jpg



PI01586A 8.1L Changes in Heads Bolts and Gasket for 2004.5 Engines: December 2003
49313244467_b412ed3f9a_z.jpg



04-06-01-018 Information on Revised Design of Intake Gasket and Related Bolts for 2004 Mid-Year Enhancement: June 2004
49313037241_9218492242_z.jpg



PIP3193B Excessive Oil Consumption - keywords bolt gasket head intake
49313244232_442b59df82_z.jpg


49312538363_502cf478e1_z.jpg
 
Here are a few bulletins and Prelim’s from back in the day that will better shed some light on the different intake bolts and gaskets. I should have added these to this thread a long time ago. I’ll go back and add these to the beginning of the thread too


02-06-01-035 High Oil Consumption: October 2002
49313037521_539a140370_z.jpg


49312538058_ed867719a4_z.jpg



PI01586A 8.1L Changes in Heads Bolts and Gasket for 2004.5 Engines: December 2003
49313244467_b412ed3f9a_z.jpg



04-06-01-018 Information on Revised Design of Intake Gasket and Related Bolts for 2004 Mid-Year Enhancement: June 2004
49313037241_9218492242_z.jpg



PIP3193B Excessive Oil Consumption - keywords bolt gasket head intake
49313244232_442b59df82_z.jpg


49312538363_502cf478e1_z.jpg

Hmm, so the part # I listed is not correct? I am 2 bolts shy of bolting on my manifold, the current ones I have are the black 72mm ones. Also my heads have blind holes that do not go all the way thru to the galley area.
https://www.wholesalegmpartsonline....-Intake-Manifold-Vacuum/2590467/11609264.html
 
Yeah, it sounds like your bolts will be too long :dunno:

I’ve also updated Post 1 with these bulletins and others

Now I am even more confused. I have my intake sitting on the engine right now with no gaskets at all. All of the bolts I do have are ran down all the way and snug. The shoulder/washer is contacting the intake and it looks like it should. And the thread engagement seems barely 5/16 maybe 3/8. I know these are smaller bolts then I am used to and the torque specs are in " lbs so this is all new territory for me. My engine is stored at work so no pics tonight but I will take a few tomorrow.
 
Now I am even more confused. I have my intake sitting on the engine right now with no gaskets at all. All of the bolts I do have are ran down all the way and snug. The shoulder/washer is contacting the intake and it looks like it should. And the thread engagement seems barely 5/16 maybe 3/8. I know these are smaller bolts then I am used to and the torque specs are in " lbs so this is all new territory for me. My engine is stored at work so no pics tonight but I will take a few tomorrow.
The whole intake bolt thing does get confusing and the sad thing is, the longer bolts didn’t do a whole lot to address oil consumption anyway.

If your heads have the blind intake bolt holes and you’re using the long bolts I suspect they will probably start snapping off as you torque the bolts down. That is what happen to the 8.1L as I was assembling it for the Suburban.
 

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