Possible engine swap into the Q

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Burnsey
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Car: '92 Infiniti Q45 ... 89' Nissan 240sx

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Well my Q seems to be putting out smoke on the rear part of the engine after running the car with a little spirit ... does anyone know what this problem is? Also I've searched and seen where Elwesso could tell if a noise was a lifter tick or not (i believe mine is) but was wondering if you could help me out with that ... I'm purchasing some BG engine cleaner which will hopefully take care of the ticking noise that's been present since I got the car at ~120k miles (engine now has ~160k miles) chains/guides were replaced at 120k miles also ....

And out of curiousity how hard/complicated would it be to swap out the current engine and replace it with another one with lower miles? I've recently done a SOHC --> DOHC swap into my s13 240sx and learned a lot about engines and about what everything does and yada yada ... but has anyone on here swapped theirs out themselves? and how was it and what is your understanding/knowledge of the VH45de ... do you think it'd be possible for me to? I have every/any tool that would be required but didn't know the difficulty of the task.


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Rex
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It's possible, but the time/effort/money spent into doing the guides and making sure all the accessories and externals (plugs, injectors, knock snesors, etc) are in top shape, go a long way to not having to do this again any time soon.

T3 uses a JDM importer in the ATL area, and it might be worth the trip to look into the head (oil fill hole) and take your pick. Also keep in mind, the miles on a used motor aren't as important to it's life expectancy as the abuse or lack of proper OCI's (oil change interval).

Good luck, and don't forget to check out the VH/VK or Infiniti Online Mechanic sub-forum for more help.

qship96
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smoke is from valve covers or pressure sensor seeping

Burnsey
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Joined: Tue Oct 19, 2004 5:17 pm
Car: '92 Infiniti Q45 ... 89' Nissan 240sx

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pressure sensor seeping? <-- completely clueless to what that is

Burnsey
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Yeah I completely forgot bout the VH/VK forum ... been looking around on there for the past hour or so trying to find some info.

M3Racer
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Is the smoke colored at all?

Burnsey
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white which equals oil i believe ... smells like burning oil.

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elwesso
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IMO the first order of business is to see how healthy your VH is... Do a compression check AND check your oil pressure (HOT at IDLE!!!!).. If both of those turn out reasonable, then i wouldnt swap the motor... However your lifter tick could be caused due to sludge/low oil pressure, or it could be just one of the HLA's has a tiny bit of varnish in it..

Dont swap a perfectly running motor if you dont need to! what may not be a bad idea is if your gonna do all that crap, is just take the motor out of the car and do it... The swap isnt that bad, main thing is unplugging everything.. Once you have all of the stuff unplugged, you just pull it out.. You can go from the top, but its easier to do it from the bottom.. Drop the engine/trans as a unit... Main hard part is you have to lift the car about 3.5-4 feet off the ground just for the motor to clear the bottom!


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hannibal
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..White smoke is usually coolant, and it would smell kinda 'sweet'. Oil is usually bluish/grey...

Q45tech
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Car: 1990 Q45 342,400 miles 22 years ownership with original engine
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coolant, and it would smell kinda 'sweet'.

If the coolant is/was ethylene glychol in 50/50...........can't assume anything.

Anyway coolant leaks into cylinders means the engine is trashed [bearings, crank, piston skirts.........warped head from overheat].

Coolant leaks are so very rare in a running engine. Bubbles and back pressure exploding rad or overflowing tank.

Most owner abuse cannot be fixed easily, takes time and treatments without total disassembly.................remove the passenger side valve cover that tells you just about everything along with compression and oil pressure.

Make sure the engine is warm when you measure compression........get it ready then recrank and run then turn of pull a plug and measure.

Old engine have low compression at cold start thus oil out back but many recover when warmed up.

Burnsey
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Joined: Tue Oct 19, 2004 5:17 pm
Car: '92 Infiniti Q45 ... 89' Nissan 240sx

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when i changed my sparkplugs awhile back (2-3 months ago) ... they were covered in oil ... would this have anything do with my problem now, or point toward the solution? ... I'll see if we have a compression tester at home and run the test tonight if we do.

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elwesso
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yeah the smoke is coming from leaky valve covers.

Burnsey
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Car: '92 Infiniti Q45 ... 89' Nissan 240sx

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am i to seal the valve cover with anything (RTF, etc.) ... ? also ... when i replaced my spark plugs there seem to have been 2-3 of the tiny allen head bolt/screws missing ... would that cause the problem? I distributed the ones i had so that it would seal the best (or at least i thought so) ... and for the lifter noise ... should I do the BG engine cleaner for engines? or?

*NOTE* - the last thing would be to swap the motor ... we have an 8 car garage outside my house and plenty of room ... so that'd be the LAST resort ... was just inquiring on the difficulty of it

ALSO Elwesso on the ECU mod for the Q45 through you guys here at NICO ... do you think it would be too harsh for my engine?
Modified by Burnsey at 11:15 AM 7/11/2006

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Rex
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IIRC, 90-93 VH45's use RTV only and 94-96 use a gasket with RTV on some moon/half-moon spots.

Burnsey
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Joined: Tue Oct 19, 2004 5:17 pm
Car: '92 Infiniti Q45 ... 89' Nissan 240sx

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alright ... I guess it might've helped me get an answer if i went into a lil more detail about my car lol ... its a 1992 Q45 incase anyone wanted/needed to know


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