VQ w/ possible blown headgaskets, how to be sure.

[Leo1998]

http://imgur.com/a/Gkd6q

Yes that's the one, or one of them. Do you think it could be that big of a leak to guzzle coolant? When you were filling your radiator was the rig running? Maybe the water pressure is high enough to force it through quickly.

[CanuckQx4]

Oh theres 2 of them eh! The truck has not been running while I fill it, when Im pouring a jug into the rad it WILL eventually fill up to the top but you can see it constantly drinking/level getting lower fairly fast, it would drop an inch in 10 seconds, pretty fast must be a sizeable passage way

[CanuckQx4]

Well, thats all she wrote for this engine boys. I pulled the intake manifolds and fought with the valve covers a few hours to get the freeze plugs exposed. Looped the coolant hoses, started filling the rad and looked for an obvious leak.

I found one on both sides, coming from a large crack stemming from the head bolts... heads are cracked.

[Leo1998]

Wow!!! both heads? Sorry to hear that. Well since you have them exposed, is it possible to remove them without taking the engine out? If so, take the heads to a machine shop and see if they can rebuild them, also compare the cost of that and buying new ones already done. I did that once and the shop welded the hole up, machined it smooth and put new valves and springs in it. That was on an old Toyota Corolla 4 cylinder. Cost? $110 bucks. Your engine is still good, just bad heads that can be repaired or replaced. Cheaper than a whole engine install, and you never know what is wrong with the next engine you get from a wrecking yard. Your compression was good right? If not, then it's not worth messing with the heads, find another engine. Trying to give you hope man! Good luck and keep us posted.

Could you post pics of the cracked heads for us to see?

[Chuck Tribolet]

And you will need to check block surfaces that mate to the heads for straightness.

Chuck

[Buzzman]

Well, thats all she wrote for this engine boys. I pulled the intake manifolds and fought with the valve covers a few hours to get the freeze plugs exposed. Looped the coolant hoses, started filling the rad and looked for an obvious leak.

I found one on both sides, coming from a large crack stemming from the head bolts... heads are cracked.

Hard to fathom why this would happen, especially given how solid the 3.5 engine has been for Nissan.
Is it possible to just pull 2 used heads from a wrecker engine?
Gotta be cheaper than replacing the whole engine, (assuming the engine block is still OK in your truck).

[CanuckQx4]

My camera doesnt pick up the cracks, the oil stained porous casting isnt photogenic lol

Replacing the engine is actually the cheapest option, I was getting quotes of 20-25 hours to remove and replace heads + parts cost. I really dont mind just swapping the engine I guess since my truck has enough miles, I found a local seller that stocks jdm VQ35de's, 40-60k average and 90 day warranty for $1250, and he works with a shop that will do the swap for $700 including fluids

[Leo1998]

That is a great deal and i would take it!
I flipped the timing chain on my old '77 Ford 4x4 and instead of tearing it down and fixing it myself, I took the 400ci out and drove it to the shop in the back of my 4x4 Ranger...lol They did the short block with a torque cam and i put the rest together with a Holly 750 and installed back into the truck for a little over 2 grand by myself...Booyeah!

[donald]

ghetto-scribe.

This thread is the best "beginning-to-end" thread I've read in a long time. I wish there was a way to "like" or "thank" this thread. I'll apologize now for illegitimately bumping the thread

[CanuckQx4]

Well your in luck Donald, just today I actually dropped the new engine into its new home in my QX4. Took over 2 weeks for Nissan to get my parts in stock, damn oil cooler gasket and water pipe orings were on backorder.

I changed EVERY rubber hose in the cooling/power steering/oil cooler system. Literally every one. Also valve cover gaskets, intake gaskets, pcv valve, loctited the power valve screws, exhaust mani gaskets.

I ended up doing it myself to, since I have the time and am pretty knowledgable with cars, this job was the biggest Ive tackled to date, and 100% on my own. I lucked out scoring a MINT engine for $1500 and a nice heavy duty engine hoist for $100. I think Im under $2000 all in after all parts and fluids.

I almost swapped 02 sensors and catalytics convertors just because mine are possibly factory, with 150k on them, but decided against it to save the bank account a bit.

Like I said I just put the new engine in tonight, got the motor mount bolts secured, flywheel to torque convetor bolts torqued to spec and a few motor/trans connecting bolts, so its sitting in there on its own atleast. Just need to do little things like starter, exhaust, wiring harness, power steering hardlines and such, a few more hours of buttoning up I guess. Fill with fluids and hope she purrs!

Glad I did it myself instead of giving it to a shop, they definitely wouldnt have taken the care I did