Seems like one thing after another with this car...

I just redid the exhaust, catback. Now I can hear the engine, not just the exhaust. Well its been 7 days since I switched to Mobil1 Full Synthetic, and 4 since I redid the exhaust. I noticed yesterday that the turbo now hums briefly for a second or two before spinning up and when spinning down then it will resume its normal whistle. After driving several miles, that brief shuddering tornado-siren like hum will go away, but come back after the car is restarted.. etc. Turbo is on its way out maybe?

 

If that sound is definitely coming from the turbo, then it is likely about to ingest itself.

 

Thought so. I've been driving really light since it started. It's usually only about a half to one second.. but I'm thinking of checking the oil pressure as there's also increased noise from the head. Any clue where the oil pressure sender is? Was thinking about plugging a meter in there. A new/rebuilt turbo would be a total waste of money if oil isn't circulating properly.

On the turbo note... Best to rebuild? Used from a junkyard? Buy new? And where can these be obtained? Just in case it decided to give up.

 

What viscosity Mobil 1 did you use? My own experience has been that turbos prefer 10W-30. At least, when they have some miles on them. I think by 87 Volvo had switched to the tiny Mitsubishi turbo for faster spool but miserable power. It would be a good time to upgrade. If you have a Garett/AirResearch T3, they are worth rebuilding. A quality rebuild kit will cost roughly $100. The best place I've found is gpopshop.com There are some kits a bit less on eBay but the guys at gpop will walk you through it if needed.

 

10w-30 and yes Garrett (I believe), Its original & i've read mitsubishi is 89+ only unless replaced.

 

T3's are definitely rebuildable but honestly, on turbobricks.com you can probably find a decent used one for 50-60 bucks. That's the price range I sold a couple last year.

 

Ahh alright, and is there a way to check oil pressure? Just for safe measure?

 

The oil light sender is screwed into the block ahead of the oil filter, by the alternator. You'll need to remove the idiot light sender and screw in an oil gauge. Not terribly difficult.

 

I didn't figure it was, I was just unsure of the location. I'll have to see if my parts store rents gauges or not...

 

Do you live anywhere close to a Harbor Freight?
Engine Oil Pressure Test Kit

 

Unfortunately not. There's one 30 miles north and 30 miles south. I could probably just buy it and have it shipped.

 

I think it had a very slight amount of play up and down.. which would make me think "hard parts" are damaged and not just "soft parts" like the rebuilt kits come with. Then again, I don't know how much movement is too much.

 

Anyone know what size the oil pressure sender hole is? I got a 3rd party gauge but im not sure which adapter to get ...

 

Okay, I'm thinking. Can a dying turbo (or one that is not free-spinning) restrict airflow and cause a loss of power on acceleration, but then be fine once its warmed up? but not cause it to stumble or die?

Also, how likely would it be that the oil passages before the oil supply lines are clogged?

Something is certainly wrong with it, It no longer whistles when spinning up. Where would be the most cost effective place to get a NEW or REBUILT turbo identical to my Garrett T3.

I have no choice to drive it till it gives out... which I hope it doesnt spew oil. I JUST redid the exhaust and oil in the intake would be a pain.

 

A seized turbo is indeed an impediment to good air flow. Add to that the fact the turbo is purposely a low compression motor, w/o boost and a clogged air passage, they are dogs. I've never seen one "loosen" up with heat but I suppose it's possible. The oil feed line will "coke" with deposits of oil. Regular oil changes and synthetic oil (resists coking) are the way to go w/ turbos. Americans are known for poor engine care...spotty oil changes will kill a turbo. When checking a used turbo's shaft for play, a tiny bit side to side is ok but there should be zero in or out. I had two really good T3's that I pulled for bigger ones but sold them recently. I could check around locally for a good used one. Some would say used are a waste of time...but $800 for a new Garrett is a bit much. Rebuilt are typically half that. A used one w/ a known history generally no more than $100. It becomes a matter of economics. I've read on here that some would have you believe a turbo should last the life of the car; that's simply not the case for most. Poor maintenance does many of them in with as few as 40k miles. Let me know if you want me to check w/ my friends and see if someone here has an extra T3.

 

I'm sure my PO was a little late for a few oil changes. It has synthetic now, and when swapping turbos out, I was planning on cleaning the feed/return lines thoroughly. And yeah, go ahead and check please. I mean, I'll check for in/out play when I put in the oil pressure gauge tomorrow. The website I was looking at for T3's was $650 new, which is a bit steep still. It will boost and everything still, it just sounds cranky and sometimes doesn't wanna go at first.

Thing with accelerating is the turbo would whistle from low rpm to high... its hard to put in words exactly. Like not only did the car feel extremely sluggish, accelerating maybe 3mph per second, but the raise in pitch of the turbo whistle was slow with it as if the oil was acting as a sludge and not a lubricant. But if you can get one in good shape at that price, I'll give it a shot.

 

There is no in/out play and side-to-side is minimal. Funny thing is today it kicked in hard today out of nowhere and felt like the car had a lot more power than I've ever gotten out of it before. xD

Kind of strange because I've never heard of such erratic behavior because of the turbo...

Is there any sure way to tell if I'd be able to rebuild it myself based on its condition?

 

For the most part, as long as a turbo hasn't frozen from lack of oil and sheared the shaft or ingested impeller blades, it can be rebuilt. To rebuild a T3, all that is needed is a big can of PB Blaster, a propane torch, appropriate wrenches and a big fawking hammer. It's best to soak the turbo bolts down with PB for as long as possible as they are very tight. The torch is to "cook" the PB deeper into the threads. The hammer is for those bolts that have developed an immunity to PB. If you have access to air tools you are ahead of the game but they aren't absolutely required. Once you have it apart you will be amazed how simple a design is the turbocharger.

 

Alright, thanks. Also, what seal kit would you recommend? G-Pop Shop Complete T3 Kit

EDIT: Nevermind, excuse my ignorance for not reading the page first. xD Needs a dynamic seal.

 

Since it's your first time, I highly recommend calling or emailing at the least. GPop was very helpful for me. They really do quality work and are quite knowledgeable. Unlike some shops who want to keep the techniques secret, they readily shared their experience w/ me. Tell them all your symptoms and go from there. Yes, I use the full rebuild kit. There are a few extra pieces that aren't needed so don't freak out when you're done! The Volvo T3 does indeed use a dynamic seal, so rebuild kit #3 for $89 is the one I'd go with.