2.7 Oil Sludge Problem

Hehe. Yea, Swiss. Sorry about that.

I've wondered about the impact of the local climate too. However these engines do run hot no matter what. Water leaving the block is controlled at between 210 and 230F. In most cars, the water leaving the block is around 190. So a cooler climate may help, but only to a point in these engines. I always thought that sludge was caused by cold temps and

There's really two types of deposits that have 2 different origins but are both termed "sludge".

1)Sludge caused by oil being mechanically mixed with water. The water can be from blow-by gases that condense in the crankcase when the engine is not brought up to full operating temp, and this happens during short trips and/or when the ambient temperature is cold. It can also be caused by a PCV system this is not operating and that would otherwise scavenge the moisture laden atmosphere from inside the crankcase (even if normal operating temps are frequently reached). The water can also be from a coolant leak into the crankcase. In both cases, the resulting sludge is a soft viscous mud, much like mayonnaise in consistency. Like a really wet, fluid mud that you could wipe away with your finger. A major coolant leak into the oil usually causes this mess to thicken up into a firmer mud as the additives in the coolant react with the oil. 2)High temperature "sludge" caused by thermal and oxidation degredation of the oil. This has nothing to do with water. This type of sludge is a black, thick, sticky, greasy deposit that does not flow, and may contain grit which is actually carbonized oil ("coke"). This type of deposit occurs where the oil is continuously exposed to extremely high temperatures. Engines with turbo chargers have problems with this type of sludge. The Chrysler 2.7 has problems with this particularly on the heads and because the coolant temperature is intentionally set high.

Put some cooking oil into a frying pan and heat it anywhere up to about

350 F, and you'll have hot clear oil. And it will stay that way for a long time. Turn up the heat some more to get the oil consistently over 400F, and watch it turn brown and then black. As the oil starts to smoke (evaporate), the oil remaining in the frying pan thickens. Eventually you'll end up with a black tar. This is what happens in engines that run hot. To avoid it, you have to either change the oil before it degrades to the point that it's starting to leave deposits (sludge), or use a different oil that will tolerate the heat without leaving deposits - namely, synthetic oil. And specifically, full synthetic made from group IV or group V oils are preferred (ie. Mobil 1, Amsoil, Redline, Pennzoil Platinum).

Phil

You probably already know this Phil, but that happens (certainly intentionally - for better emissions purposes, according to the FSM), or should I say, is designed to happen, by their having put the thermostat (180°F from factory) at the coolant inlet end of the block (radiator outlet) rather than the engine outlet (radiator inlet) as in traditional designs.

That *precisely* describes what used to totally clog up (and actually dissolve a hole in the rubber elbow of) the PCV hose on mine before I replaced the PCV hose with the later design (with heat exchanger).

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Yes, I've used Mobil 1 since the mid 70s for exactly that reason. I probably don't really need it for 99.9% of my driving, but I do like the much improved cold weather starts as well. Although, I must admit that the new 5W20 dino oils being used have closed that gap significantly. Me new Sonata came with 5W20 and it spun pretty good even down to near zero. When I switched to Mobil 1, the difference wasn't dramatic as it was years ago when 10W40 was all the rage.

Matt

I hadn't heard about this design feature before. That is simply nuts. If the radiator is effective at all, you could easily drop 30-40 degrees across the radiator meaning that the engine might be seeing water temps of 210-220 before the t-stat even opens! Once fully opened, it shouldn't matter as much where it is located as far as what the water temps will be, but that certainly seems like a dumb design.

Does the sludging Toyota engine have this same design?

Matt

Phil T wrote:

I bought an Accord brand new in 1984. It was my first new car ever. I bought it based on the raves in Consumer Reports and other places. It was the worst POS I've ever owned. It had two recalls during the first year (AC schraeder valve leaked and the cruise control release valve didn't have a drain hole for moisture and would freeze in the winter - meaning you just kept going faster and faster after every hill!). It was then decent until the 4 year, 60,000 mile point when it needed new struts all the way around (my minivan went 178,000 on the OEM struts), new disks and drums all the way around (they rusted terribly - my US cars easily go 100K in these parts), a complete new exhaust system (rusted away - my Acclaim was still original at 143,000 and my minivan went over 150,000), and a bunch of other stuff. However, the coup de grace was when the camshaft and rocker arms failed at 72,000 miles. The cam lobes were worn more than 1/8" (probably a third of their lift height) and the pads on the 16 rocker arms were similarly worn. Since the car was out of the 3/36 warrantly, Honda said "so sorry." And when I complained to the zone office, they wrote me a nasty letter accusing me of not maintaining the car. When I send them a copy of my extensive maintenance and fuel purchase log book (I record EVERY gas purchase), they wrote back and said that it didn't appear that maintenance was the issue, but that 72,000 miles was within the "expected engine life for a Honda given normal manufacturing tolerances."

Well, that is the only engine I've owned in 30 years of car ownership that didn't easily make 100,000 miles. That was the first, only and last Honda that I have ever owned or will every own. They've lost at least five new car sales since then (and that is just my purchases, not relatives and friends that I've steered away from Honda) due to their complete lack of customer service. I realize that crap happens and this may well have been a fluke, even the more reason that they should have at last met me halfway. Even if they had offered to buy the parts, I probably would have tried one more Honda.

However, there are just too many choices today to have to deal with a company like Honda. My experiencd thus far with Hyundai has been just the opposite from Honda. They almost drive you nuts with customer service.

Matt

Not sure about Toyota.

For your viewing pleasure - right out of the ('99 LH car) FSM:

That applies not only to the 2.7L, but the 3.2 and 3.5L engines used in all 2nd gen. LH cars. It's funny reading the FSM because you can see that old habits are hard to break - a couple of times, they slip up and refer to the engine coolant outlet housing (where the thermostat would traditionally be on an engine) to the "thremostat housing".

Kind of reminds me of the '85 or '86 (I forget which) Subaru GL-10 FSM that, in the turbocharger section, when talking about the waste gate refers to it a couple of times - I swear I didn't make this up - as the "watergate". I don't know if it was a subliminal honest mistake or if the translator was having a little fun . But I digress...

The LH car FSM says (regarding the thermostat on all three 2nd gen. LH engines): "The thermostats are located in the inlet side of the engine to provide fast warmup and to optimize a constant temperature in the engine." Perhaps you'll be glad to know that "[t]he thermostats have an air bleed located in the thermostat flange". That should help to moderate that startup spike a little I would think.

I've mentioned this before here, but you obviously haven't been paying attention. You're supposed to hang on my every word. :)

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

I don't see how this affects the rate of warm-up. Water won't flow whether the t-stat is at the inlet or outlet as long as it is closed. The engine will warm to a higher temperature with the t-stat on the inlet, but I don't see how it can warm up any faster.

Oh the shame... :-)

Matt

Oops - obviously that should have been "thermostat housing". Darn - messed up a good story.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Hey - I'm just the messenger! Seriously, that heater return hose coming back into the thermostat housing does serve as a bypass, and the FSM refers to it as that. That may buffer things with the smaller mass of coolant in that loop, and may be what actually opens the thermostat initially.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Actually I had 2 83 Toyota tercel 4 WD wagons. Great cars but even though I kept them garaged, if I didn't keep those carburators absolutely clean they would never start in cold weather.

One thing I've noticed about my 2 new Hondas is how incredibly quieter they are. I don't think it is anything magic. It is different steel compared to most cars. Bang a body panel on any car versus a honda. It is much quieter. My understanding is that Volvo's also use different steel and even though Ford is using the same platform for Volvo's, Fords and Mazdas, only the Volvo's have the extra strong steel.

Hi...

Dunno, cause I can't use mileage for the criteria... if I did I'd be ready for my next change in a few years :) Probably nowhere even near 2,000 miles a year :)

Willing to hear advice, though, if anyone's willing to offer it...

94 lhs 3.5; like brand new in (almost) every respect. I imagine that properly taken care of it'll last me as long as I have need of a car.

Resources to replace all the oil I want are available, but I come from the waste not/want not generation, so...

Live in Winnipeg (Winterpeg), Canada, where winter temps of

-40 aren't too unusual, and summers of +90 F aren't either. Being old and retired, I can pick my days in the winter, so go on the warmer ones. Also plugged in for a few hours before going, followed by 5 minutes or so of idle warm up. Despite that, never get the engine good 'n hot.

So - using good quality 5w synthetic, change it how often?

3 months? 6 months? Yearly? Or when it discolors, or smells a little unusual, or feels a little odd between my fingers?

Opinions appreciated, thanks in advance.

Take care.

Ken

Yea,I've read all about it in the FSM. For emissions and thermal efficiency, it certainly seems to work. Hard as hell on oil and bearing though.

Phil

Ken,

We Canadians have the perfect oil for the Winnipeg climate and it's only available in Canada: it's Esso Extra XD-3 0W-30. Heavy Duty Full Synthetic (PAO, just like Mobil 1), loaded with the highest detergent levels you'll ever find, and only half the price of Mobil 1. Pumps down to -49F or something like that. Usually only available from Esso Lubricant Distributors - check the Yellow Pages. It's listed as a diesel engine oil but it carries all the necessary API designations for automotive use. Fantastic stuff. It's used extensively out your way by those who know about it.

There's a guy either in Winnipeg or Regina (can't remember which) that owns a "Taxi" service with a half dozen or so Chevy mini-vans or whatever they're called. He runs this oil for 25,000 km oil change intervals, gets the oil analyzed at each drain and often posts the results over on "Bob Is The Oil Guy" (BITOG). Fantastic results in the analysis, and he runs these these vans to 600,000 + km before he retires them.

Get some ! I have a case of it in my garage but haven't used it yet due to other experiments in the oil dept at the moment. It's actually a little on thick side for the 2.7 so I might have to cut it a bit with a

0W-20 or 5W-20. But it would be a good fit for the 3.5.

There's nothing wrong with your Castrol Syntec - it's reasonably good stuff. But for about half the price you can actually get a far better oil (the XD-3). And that Fram " synthetic" filter - if that's one of the XG series, it's actually an excellent filter. And about the only decent filter that Fram makes. Avoid the rest of the Fram filters.

The American members on BITOG drool over this XD-3 but they can't get their hands on it.

Phil

PS. I've been in Winnipeg several times in December and January and all I can say is that weather ain't funny at all. "Gee, it's going up to minus 26 today. But it'll be a little chilly tonight with the temperatures falling to minus 38, or minus 49 with the wind chill ". C'mon - why do you guys even live there ? The rental car was like a block o' concrete in the morning. The lobby doors in the hotel had 1/4 inch of ice on them - on the INSIDE. If you drive around the block quick enough, you can drive right through your own exhaust plume - it's still there from where you started out. Jeez !

There's no need for this. Just move away from there. C'mon down to southern Ontario where it's warm and we only get an inch of snow at a time. Hell, if the overnight temperature drops down to +5F here, they're ready to declare an emergency. And so they should. We pay a lot of taxes down here and those temperatures shouldn't be allowed.

Because the T-stat has cool/cold water on it from the radiator outlet hose, so it won't open until the jackets have fully heated up and then the heated water has made it's way through the radiator and eventually back to the inlet of the T-stat. Actually I guess the Bypass flow through the heater hose ultimately supplies the first warm water to the T-stat. But that water is supplied from the outlet of the block.

Phil

But the jackets won't heat up any faster just because the thermostat is at the inlet. The only way this can make a difference is if water is somehow flowing through the engine prior to the t-stat opening. I didn't think this was the case even with an outlet mounted t-stat, but maybe it is. Keep in mind the comment was about the rate of heat-up, not how hot the engine would get before the t-stat opens. I agree it likely will get hotter with the inlet mounted t-state, but I don't see it getting hot any faster.

Matt

I suggest at least every 6 months, early spring and late fall, regardless of the mileage driven or oil type used. In the case of your very cold winters with short drives I'd probably do another change mid winter.

Hi Phil...

Great info; thanks very much! :)

I've already found a source at only 3.09 a liter, in a town here in Manitoba called Lac du Bonnet - which happens to be the nearest town to the cottage :) I'll grab a case of 4 x 4 next weekend :)

Hey, Winnipeg isn't so bad... I was born here, but moved to Toronto (Oakville) for higher education and stayed there to work (ctv) for a lot of years. Eventually lost a child, had a heart attack as a result, and came back here.

We do get used to the weather, and actually enjoy the change of seasons. The variety is nice, and we learn a few little tricks that make the extremes much less unpleasant. A tiny example might be to keep the humidity indoors low enough that moisture doesn't condense on windows and doors to freeze. Which in turn means that when we (too humid) get into cold cars the windows don't immediately do the same thing :)

AND the lower temps mean that salt isn't effective, so our cars don't rust away nearly as badly as yours do :)

And if you were here for any length of time, you can't have helped noticing that the people and lifestyle are very very different...

Thanks again for the info, and take care.

Ken

I'm not living in Winnipeg, but I lived in Southern Ontario for 10 Years and have visited Winterpeg during a -35° period. It's doubtful they would trade their clear air, regardless of the temperature, for smog-ville.