Engine

[AlexM]

Hello. I am new to this forum-thank you for including me. 

My 93 Pathfinder is suffering from broken exhaust manifold bolts. I read several message on this issue, here, where i learned it's a common problem, and very difficult to solve. In my case, it's on the driver's side, where there is even less access to work on it. 

The motor has 240 K miles, and some change, so I have been searching for an engine, hopefully with fewer miles, or perhaps someone willing to overhaul my motor. 

I have had mine for around 10 years and want to find a way to save it from going to the wrecking yard. 

Any ideas on what my options are? Thank you. 

 

[peejay]

a - find a VG33 parts engine and use its cylinder heads (drill your exhaust manifolds to fit the larger studs)

b - find a VG33 engine and use it, Frankenstein parts from your VG30 engine (crankshaft stuff)

c - find a VG33 engine and swap it in (reuse your VG30 oil pan, have someone cut and braze the AC lines to mate the VG30 lines with the VG33 compressor)

 

Plenty of good writeups around however you decide to proceed!

Edited May 30, 2024 by peejay

[Slartibartfast]

Mine's needed this done for longer than I've had the truck. I bought gaskets, studs, and a 90 degree drill adapter shortly after we got the truck, and then I never got around to it. My engine is also a little tired, and the rear main is leaking, and I've got a VG33 in the corner waiting for me to get around to it, so chances are I'll keep ignoring the exhaust leak until I'm ready to swap the engine.

 

The VG33 has a little more displacement, larger exhaust manifold studs, a larger crank snout, a better oil filter location, and a couple of other minor improvements. It's mostly bolt-in, and will run off the stock harness/computer/fuel system if you swap a few things over from the old engine. It's also got flat belts, and a different balancer, so there's a little screwing around required there. David Carroll/Mr. 510 makes (made? Don't know that he's still selling them) adapters that replace the balancer so you can run the old V belts and accessories. You will need to modify a VG30 water pump if you do it this way. (Details in Mr. 510's VG34 build thread.) I have read that the Xterra/Frontier accessories and brackets will fit in the WD21 engine bay, but the R50 Pathfinder ones won't, though I think someone managed to make them work with a little modification. I have heard of people swapping the VG30 crank into the VG33, to keep the old balancer, but it sounds like a lot of work to use an inferior part (the smaller snout of the VG30 crank does sometimes have issues). The VG30 cams are supposed to be a drop-in upgrade over the VG33 cams, so hold on to those. The oil pan and pickup may need some screwing around depending on your donor.

 

I've read that VG30/33 heads can be swapped, but the cooling passages are a little different due to the larger bore, so it's not exactly ideal. If I was going to pull a head, I'd just fix the old head on the bench (without a truck in the way!) and then put it back on.

[peejay]

43 minutes ago, Slartibartfast said:

I've read that VG30/33 heads can be swapped, but the cooling passages are a little different due to the larger bore, so it's not exactly ideal. If I was going to pull a head, I'd just fix the old head on the bench (without a truck in the way!) and then put it back on.

Yes, everything start said!

 

(I didn't know about the water passages/larger bore, I thought they just increased the stroke. For that much trouble, I'd just swap the entire engine.)