Suggestions for engine replacement project

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92Q45_Greenish
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Joined: Wed Jun 14, 2017 8:13 pm
Car: 1992 Infiniti Q45 115000 mi

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Hello fellow Q45 fans!
I promise I've searched the forums to see if anyone had already covered this topic and found none.
I have a '92 Q base model with serious engine issues - 2 cylinders with 0 compression and 2 more that are low.
I searched and found an engine in a nearby salvage yard and the junkman practically gave it to me because he hadn't been able to sell it. Its a '92 Q engine and he promises that it was running but it also has about 200K on it. The engine looks like its been worked on - water pump has red RTV and so do the valve cover gaskets. The front driver side of the head shows signs of an oil leak but the passenger side is clean.
I'm looking for advice on preparing to swap the engine. What would you suggest? My mechanic said he would do a "leak down" test first to see what he could tell about the engine and we would go from there. Assuming all is well, I want to replace the timing chain guides - can't tell whether that has ever been done.
Planning on replacing the coolant hoses beneath the plenum and also bring over the practically new injectors from my old engine.
What would you do before installing the engine??


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Q451990
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Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
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At a minimum I'd go ahead and remove the valve covers and reseal them. That burnt orange colored RTV is probably the Nissan factory stuff that the dealership techs used. If the front cover still has the factory baby blue colored RTV that's really neat, you can be pretty sure the front cover hasn't been off - and you're dealing with original guides. If the guides are broken up, be sure you can match up all of the chunks you can find to make full guides. If not, I'd pull the oil pan and clean it out while the engine is easy to get to. Rear main seal would be a good one to replace now too.

92Q45_Greenish
Posts: 10
Joined: Wed Jun 14, 2017 8:13 pm
Car: 1992 Infiniti Q45 115000 mi

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Thank you so much! I'm going to post some pics soon before I start anything. Thanks for mentioning the rear main seal - I'll add that to the list - wouldn't you do the front one too since I'm doing the timing set?

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Q451990
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Joined: Tue Jul 23, 2002 8:21 am
Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
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92Q45_Greenish wrote:
Sun Jul 09, 2017 2:09 pm
Thank you so much! I'm going to post some pics soon before I start anything. Thanks for mentioning the rear main seal - I'll add that to the list - wouldn't you do the front one too since I'm doing the timing set?
Looking forward to the pictures. I'd certainly pull at a minimum one valve cover, even if the compression test comes out OK, just to be sure you're not dealing with a sludged up engine. I understand the appeal of the almost free engine, but you're putting a lot of effort and $$ into an engine with that mileage - so I'd do as much cheap investigating before you bolt new parts to it. The front main should be done too... I'm pretty sure it's supposed to be replaced any time the front cover comes off.

92Q45_Greenish
Posts: 10
Joined: Wed Jun 14, 2017 8:13 pm
Car: 1992 Infiniti Q45 115000 mi

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about those pics - I am not sure I have found current info about posting photos. I see an article about using Photobucket and then newer comments that say Photobucket isn't a good choice anymore - can you point me to the right info fro photo posting?
I see you are just down the road in the "other Carolina" :) I'm in the northwest corner of North Cackalackey - so not too far away! Thank you for your replies! I sure hope we can get this slick ride back on the road. It sure is sweet and becoming more rare all the time!

EdBwoy
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Signature below, except photobucket.

92Q45_Greenish
Posts: 10
Joined: Wed Jun 14, 2017 8:13 pm
Car: 1992 Infiniti Q45 115000 mi

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OK thanks a bunch!
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Q451990
Moderator
Posts: 11030
Joined: Tue Jul 23, 2002 8:21 am
Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
Location: Columbia, SC
Contact:

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92Q45_Greenish wrote:
Mon Jul 10, 2017 6:50 pm
I'm in the northwest corner of North Cackalackey
Yeah, we have a bunch of yankees posting on here... :facepalm: :chuckle:

Pictures look interesting. I'd certainly do those compression tests and check under the valve covers before you get too far in to it... it's a total crap shoot at this point, so the more you learn before spending big $$$ the better.

92Q45_Greenish
Posts: 10
Joined: Wed Jun 14, 2017 8:13 pm
Car: 1992 Infiniti Q45 115000 mi

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Yes indeed! Thanks again for your feedback and help with pics!


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