97 Autobahn overheating -

[akble]

My 97 has 140K and besides the normal problems with Auroras been a great car. Recently had her out cleaning the pipes after long winter and she overheated after about 20 miles. Filled with water and limped home.
Over course of next couple months she started doing in fairly regularly at normal speeds after 20 miles or so. Runs fine with not hesitation or water on dipstick. Perhaps a little out tail but hard to know for sure in winter. No noticeable leaks when parked.
Mechanic thought it was probably a problem in head and gave it dose of K&W Fiberlock. Followed instructions and drained radiator and such. Seemed to be ok for couple weeks then out of no where thermostat took off. Took back to mechanic and really low on water. He filled it and said the radiator cap was bad and replaced that.
60 miles later found that was not the problem. Plus now the heater was intermittent , still using water, overheating but no noticeable performance issues.
He changed thermostat and drove 30 miles and said no problem. I then drove about 15 miles and the guage was all over the place- would go from 200 all the way to just before first red marker then seemed to hold there. Slowed to 45 ran the heater full blast and she dropped to 220 for about 5 miles then started back up.
Arrived at my destination - was down gallon in radiator - filled it and started home hour later. 20 miles at 100-210 and held at the 210 the last half. Pulled away from stop sign and started climbing slow for next 8 miles till reaching the red and stopping at first marker as I reached town , The last 2 miles at 20-30 mph and she dropped to 250 or so.
Mechanic run it up on hoist and said appears to be leaking out seal on back of engine and would be areal ***** to change - essentially removing the motor to get to it. Did not get feeling he wanted to screw with 20 year old car any more.

Any suggestions, observations or ideas? I love the car and tough finding another online to replace it . Driven several new cars - Maxima, Lacrosse, Impala, Avalon - all different and nice but none have any better ride than Aurora with new tires, struts, rear shocks, brakes, alternator , compressor in the last 10K miles. And none have a Northstar !

[plato442]

It sounds like head gasket failure. Time to make a serious decision! I too had to make that decision and of course decided to throw in a 4.6, and upgrade the head studs. Been 5 years and no issues and countless smiles!

[aphex]

Have you checked the metal purge line and hollow bolt? Follow the small line coming off the side of the coolant reservoir. I would try to clear using compressed air & a weed wacker line - I wouldn't bypass as some people suggest online. The line runs through the throttle body to heat the air, so bypass only to keep the car running in the short term, or risk eventual problems.

[plato442]

Mar 5, 2018 20:24:33 GMT -6 aphex said:

Have you checked the metal purge line and hollow bolt? Follow the small line coming off the side of the coolant reservoir. I would try to clear using compressed air & a weed wacker line - I wouldn't bypass as some people suggest online. The line runs through the throttle body to heat the air, so bypass only to keep the car running in the short term, or risk eventual problems.

OP mentioned that his mechanic saw coolant leaking from a back seal. Doubtful it’s the crossover purge pipe

[tigger]

Mar 4, 2018 15:13:32 GMT -6 akble said:

Mechanic run it up on hoist and said appears to be leaking out seal on back of engine and would be areal ***** to change - essentially removing the motor to get to it.

I'm assuming you (and/or your mechanic) are referring to the "back" of the engine as the firewall side? If so, I think there is a freeze plug (or 2) back there, otherwise it's leaking from the head gasket. Neither easy to get to.

But if you're referring to the actual back of the engine (driver's side of the car) where the water pump, thermostat, and crossover seals are, then yes, he is tired of working on your vehicle. Or, just as likely, has no idea what he's doing...

[akble]

Actually Tigger he is pretty good mechanic. Has had to pull this engine couple times when I first bought it. He is good friend but does not share my enthusiasm for Auroras. Tells me he has a line on a good pickup or van that I should switch to.

Like me he is over 60 and I think has no desire to do this job. He says the water is leaking out the rear of the head - I presume he means on the firewall side.

He also has always treated me real right on price and I fear that is part of reluctance thinking it is not a profitable venture . I will search around to see if anyone else is interested in tackling it.
It appears there are some advertising doing it for a couple grand on eBay however not close enough to make it practical. Is that a fair price to look for locally or to offer my friend to fix the head including parts ?

Thanks for all the input from everyone . Love the car but not that technically comfortable with it.

[tigger]

Sorry to offend, didn't realize he was a personal friend. Just a product of my deep rooted disdain of unqualified 'mechanics'.

I wouldn't consider 2-3k out of the ballpark for that repair, as long as the repairing shop realizes that block damage is likely with head removal, AND repair or conversion to head studs is included.

But, there are remanufactured, head studded engines available from several vendors if you're willing to spend a little more...

[wfooshee]

Yeah, if it's coming from the head gasket, it's a very involved repair, and whoever's doing it has to really want it to be done. With the overhead cams and all that timing gear, plus the aluminum instead of iron (which is why the head bolts won't come out clean - they bring part of the aluminum threads with them,) you're looking at pulling the motor and disassembling the top end; not for the faint of heart. May as well do both heads while it's out, as the labor to get there is already done. Now you've got threads to repair, studs to install, new gaskets all over the place, and reassembly, which means timing the camshafts correctly.

Or pull the motor and replace it. Is the replacement OK? Hard to check it without installing it...

I love the car, but if mine reaches that point, it's done. Gone. Outa here! Not worth the effort. Not gonna spend more money on a repair than I paid for the whole damn car in the first place!

[akble]

appreciate your post wfooshee and is definite consideration. My problem is the car is in excellent shape, runs and drives very good - after test driving new cars @ 30K$ not found one that offers any better ride, mileage or engine performance than the Aurora for an extra 25K$ for my needs.

So am at decision time - repair? probably not the best choice locally, replace with used low mileage engine with 77K miles laid in around $900 with 5 yr warranty , find a rebuilt for 2-3 times that or junk it ( not sure I can do that).

Any suggestions on these choices would be greatly welcome. Used low mile engines with guarantee a big gamble? Rebuilt engines - any recommendation? Repairing this one not a good option locally I fear

[RCA1186]

It sounds like you're not ready to give up your car yet. I'm dreading the day that I have to make a decision like this. But based on your responses I would say go for the rebuilt. Maybe contact lanceslambos and see where he got his motor. The 77k mile motor could be fine, or it could have the same problem as yours or something worse...no way to know. I guess you have to decide whether it's worth the $900 gamble, although a 5 yr warranty is pretty useful.

[akble]

simple question but don't seem to easily find answer in Archives. Will 4.0 "C" engine from 93 Aurora swap into a 97 Aurora?

[tigger]

Apr 4, 2018 19:38:41 GMT -6 akble said:

Will 4.0 "C" engine from 93 Aurora swap into a 97 Aurora?

'93?

[RCA1186]

Apr 4, 2018 19:38:41 GMT -6 akble said:

simple question but don't seem to easily find answer in Archives. Will 4.0 "C" engine from 93 Aurora swap into a 97 Aurora?

Aurora only comes in '95-03. Although the '95's would technically have some made in 1994.


A '95 motor will fit in a '97. But it is on OBD 1 (1.5) and 96 and up are on OBD 2. What this means is it will physically fit, but might be an electrical nightmare to make it work. I/e- sensors with different plugs, sensors that exist on the '95 but not on the '97 and vice versa. Could you make it work? Probably, but it'd be a pain. You'd be better off getting an engine from a '96-99. Any from those years should bolt right up and plug right in. Best bet is to find one from a 97-99 as these will be the most updated and might not need things like the fuel rail recall, etc.

[akble]

my bad - I obviously meant 2003 Aurora not 93

[RCA1186]

2nd gen motor (01-03) will not work in a classic.

[tigger]

Apr 6, 2018 12:56:21 GMT -6 RCA1186 said:

2nd gen motor (01-03) will not work in a classic.

Well, not with that attitude!


But yeah, no.

[akble]

Thanks - not sure what was meant by attitude though?

[tigger]

Apr 7, 2018 12:17:07 GMT -6 akble said:

...not sure what was meant by attitude though?

Jokes man, just jokes! Google it!

All apologies.

[lanceslambos]

Look at your inbox. I replied to you akble. A 2-3K dollar engine with a warranty is doable but without the warranty I wouldn't consider it. The issue then becomes finding a mechanic who will tackle the engine swap. You'd think more mechanics would work on these but 90% will refuse. All northstars suffer from this issue and it doesn't matter if they have 30 or 300k miles. Blue Devil is probably the best snake oil mechanic in a bottle since you can use it multiple times or with other similar products. Good luck.

[mattn]

Mar 5, 2018 8:32:51 GMT -6 plato442 said:

It sounds like head gasket failure. Time to make a serious decision! I too had to make that decision and of course decided to throw in a 4.6, and upgrade the head studs. Been 5 years and no issues and countless smiles!

What did the swap to the 4.6 cost?

Did you take out the head bolts from the 4.6, and replace them, before installing the 4.6 in your car? Wouldn't that have required replacing head gaskets, since you loosened the head bolts?

[catfish]

My '97 has had issues over the years. Water pumps, hoses, etc. I replaced the Crossover gaskets two years ago when I went over 100K. Just didn't want to have that problem later. And as described by others it's an involved process. You have to remove everything on the drivers side of the engine including the throttle body and the shift linkage. It's a lot of different socket set ups involved too.
Here you see the parts removed prior to gasket cleaning on the block and heads. The Throttle Body is resting on the top.


While I had all of this apart I should have replaced the heater core supply/return hose assembly P/N 25642183 but I didn't have the part. So last week I finally replaced that, and none too soon. It was starting to spray from the supply side at the firewall connection. But seeing where it was leaking was not easy. I had to remove the brake vacuum can to get access to replace it. That's another sad story. The Vac Can lower left nut is near impossible to access.

All good now and no leaks.

[ljhermsen]

That is indeed a tough job. Thank God for Gearwrenches. I did this to a 2003. Didn't videotape anything because of the overabundance of swearing involved.

But when it's ALL done and works perfect again, that is an extremly great feeling and accomplishment.