3.0R wrecker engine showing signs of blown heads...

Posts specific to the 3.0 litre NA H6 engine

3.0R wrecker engine showing signs of blown heads...

Postby Paul17041993 » Fri Dec 13, 2019 12:12 pm

So in summary, I have an MY04 outback with a bit over 280,000km on it, great car, however the original engine in it recently blew apart the radiator cap and had obvious signs of blown heads. So we ended up having the engine replaced at a wrecker with one with about 150,000 on it, "tested good".

Pretty much immediately after getting the car back, it had overflowed the overflow tank and was constantly bubbling gas out after >20m of driving, on a warm day. No overheating. I'm sure most of you know what this means...

So got into contact with them, they sent a mechanic down to test it, put the funnel on the radiator (which was practically empty at the time), topped it and started the engine. For the next 10+minutes it would be constantly pushing big bubbles every 1-2 seconds out...

Mr mechanic then stated that he "didn't see any bubbles come out"... :? but then decided to get under the car and drill holes into the thermostat as he believed there was a 'blockage' (yea, doi, it had only been running for 10 minutes, hadn't even warmed up yet...)

So he did so, topped it up, took it for a drive and it was "fine", so then I took it for a drive myself (pushing the torque up this time of course), and sure enough the overflow overflows and bubbles while running at optimum temp.

So the mechanic gives up, goes home but asks for a check-back as to whether the coolant had returned hours later, which it didn't of course because it's now full of 'air'.

They towed it to their shop... and replaced the thermostat and radiator cap... stated it was now fine and ready for pickup... ok... except we already established the thermostat was fine (albeit destroyed now and needed replacing anyway), and the cap was brand new and of-spec as far as I know. If the cap was under-pressuring the radiator hoses wouldn't be growing the way they were, and over-pressure wouldn't simply be letting everything out anyway...


I'm basically 100% sure at this point, if I go there to pick it up I'll immediately have it show head issues yet again, and being an hour's drive there and another hour back...

So what's your opinions on this? the wrecker is highly regarded but I'm not going to mention who they are at this stage, their experience with EZ30's at this point seems very questionable though.
Paul17041993
 
Posts: 3
Joined: Fri Dec 13, 2019 11:41 am
Car: MY04 EZ30R outback gold premium

Re: 3.0R wrecker engine showing signs of blown heads...

Postby flatsix » Fri Dec 20, 2019 3:41 pm

Hi any luck with engine during the week? Does she idle ok for 30+ minutes without the dash temperature gauge going above horizontal?
flatsix
 
Posts: 9
Joined: Sun Aug 26, 2018 7:04 pm
Car: 2007 Ez30r Outback

Re: 3.0R wrecker engine showing signs of blown heads...

Postby jeb » Sat Dec 28, 2019 9:58 pm

Hi all

Ha, I find myself in the same boat. Maybe we should get together and pour a beer :lol:

Bought a supposedly good used EZ30R (80,000km) 90 days warranty from a reputable Melbourne wrecker.
Install it myself, fitted a new cap & thermostat.

Motor seemed good enough for 5-6 weeks. Then overflow tank began filling up and heater core gurgling. Topped off the radiator and bleed using a spillfree funnel. A 20-30min drive has the air returning to the cooling system and overflow filling up. The new engine hasn't been overheated, however the coolant temps using Torque Pro seem high, 94-100degs while cruising on a 25deg day. Have pressure tested the cooling system at 16psi (limit of cap). It holds pressure and I can't see a drop of coolant leaking while under pressure.

Pretty sure it's headgaskets failing!

Maybe as a last ditch effort before warranty call, could install new radiator, upper and lower hoses & set of screw type hose clamps. Even though pressure test held up, perhaps the radiators plastic end tanks could suck air into the system?

Any clues?
jeb
 
Posts: 2
Joined: Sat Dec 28, 2019 9:26 pm
Car: 2005 Ez30r Outback

Re: 3.0R wrecker engine showing signs of blown heads...

Postby subyroo » Sun Dec 29, 2019 11:31 am

jeb wrote:Hi all

Ha, I find myself in the same boat. Maybe we should get together and pour a beer :lol:

Bought a supposedly good used EZ30R (80,000km) 90 days warranty from a reputable Melbourne wrecker.
Install it myself, fitted a new cap & thermostat.

Motor seemed good enough for 5-6 weeks. Then overflow tank began filling up and heater core gurgling. Topped off the radiator and bleed using a spillfree funnel. A 20-30min drive has the air returning to the cooling system and overflow filling up. The new engine hasn't been overheated, however the coolant temps using Torque Pro seem high, 94-100degs while cruising on a 25deg day. Have pressure tested the cooling system at 16psi (limit of cap). It holds pressure and I can't see a drop of coolant leaking while under pressure.

Pretty sure it's headgaskets failing!

Maybe as a last ditch effort before warranty call, could install new radiator, upper and lower hoses & set of screw type hose clamps. Even though pressure test held up, perhaps the radiators plastic end tanks could suck air into the system?

Any clues?


Were the new cap & thermostat both genuine items?

I have heard of Subaru's being pedantic with aftermarket parts.

The temp needle on my Forester used to live 1 needle thickness below the 1/2 way mark, that was until one hot day I was towing a trailer with a golf cart on it at 80 - 100 km/h, I was lucky to see the needle rising quite quickly to just below the red zone. I pulled over and let the engine cool off and then crawled home at 40 - 50 km/h, with a close eye on the temp gauge.
I took the car to my mechanic who tested everything on the cooling and heating system and found that the bottom portion of the radiator was blocked with very fine sand, ala casting. The only water that went into the that radiator (very rarely ever needed any) was rainwater.
A radiator specialist couldn't even budge the sand from the cores, new radiator and everything was good again.

From memory 94 - 100 was in the range of where my '03 XS Forester used to run, I had an Ultragauge permanently connected to my Foresters OBDII. My mechanic told me that once the temp needle moves on a Subaru it doesn't take long to reach the red zone and by then it can be too late.
Pedro

2021 Honda HR-V VTi-S
MY03 XS Forester (owned for 13yrs.)
Man blames fate for other accidents but feels personally responsible for a hole in one.
User avatar
subyroo
 
Posts: 370
Joined: Thu Feb 05, 2009 7:30 pm
Location: Sunshine Coast
Car: 2021 Honda HRV VTi-S

Re: 3.0R wrecker engine showing signs of blown heads...

Postby Paul17041993 » Sun Dec 29, 2019 2:59 pm

Bit of a late response, but as it turns out they then replaced the radiator as well, making that 2 new caps, 1 thermostat, 1 radiator and the main fan relay (only has one). Only thing that hasn't been replaced on the front now is the fans and their control box, both of which are fully functional.

They took it for multiple test drives down the local highway, and it came back "fine", though I doubt they actually popped the hood and checked it...

Convinced me that it was good to go, had not got any official testing documentation yet, but I basically decided to go up there and check myself, as at this point they couldn't seem to see the issue. Sure enough...

Got in the car, started up, it was already at optimal temp (they tested it just an hour beforehand)... and immediately I noticed a 'ticking' on the steering wheel... "oh this is going to be a fun, short trip.

Decided to ingnore it for now, drove it out the driveway and proceeded up the hill to the main road, watching the temp guage, get to a little bit of traffic before the intersection...

Guage was 1mm above the normal spot... 2mm... 5mm... aaaand zoom to redline... coolant was everywhere...

Ok, joking about the coolant part, but it definitely was bubbling with the overflow at its peak. Parked it just on the side and went back down to the shop, guy came to look at it and after a bit of demonstration with stall-throttling it, sure enough the overflow was spewing with gas way more than it ever had before.

So in summary they've booked another engine replacement first thing in january, so we should hopefully be out of this scenario pretty soon. The fact that I could feel a ticking motion in the wheel was quite surprising though, prior to it being sent back, and with the older engine as well, the worst I got was a general engine rumble similar to a straight-4. But in this case there was a little rumble, but with an additional little thud that ran in exact timing with one of the cylinders. Seems as if the test trips were just enough to pop that one cylinder just enough to compromise the engine completely...

Hopefully they actually go through the effort of testing the next engine properly, not that it's any extra cost to me other than wasted time...

jeb wrote:Maybe as a last ditch effort before warranty call, could install new radiator, upper and lower hoses & set of screw type hose clamps. Even though pressure test held up, perhaps the radiators plastic end tanks could suck air into the system?


I'd say it's a warranty run, these engines have the water pump built internally behind the timing chains, so basically the only place gas can get in is the heads. Air could come in via the radiator ends and hoses, but only when its all cooling down, and only if you had a bad cap really. You should notice cooling loss on said areas before I think it would be bad enough to suck air, but also the hoses would likely collapse in the process (ie a cap not resetting to neutral when the pressure drops).

There's these cheap radiator funnels you can get, I think I got mine from supercheap, where you basically just shove it into the cap hole, top it up if necessary, and start and bleed the engine of any extra air. Having it on an incline helps, set the heater to maximum heat and fan speed and squeeze the top hoses every so often, if the engine's not blown you shouldn't get any bubbles or rising coolant after it heats up. Last I checked the thermostat is supposed to open for an optimal temp around 70-80C, which is not nearly high enough to boil the coolant.

If there's some regular bubbles, or even some little tiny 'foam' bubbles coming up, give the engine a rev and see if even more come out. If they do then a head has been compromised.

For automatic trans cars, you can do an extra trick that I mentioned above, where you basically put it in reverse (or drive on an incline), hold the brake pedal hard as well as keeping the handbrake on, and rev it up. Rev it slowly in the off-chance it starts to spin a wheel, but at least in the outback ECU it hard-limits the RPM to 2K, no higher. The accelerator basically dead-zones at 2K because the ECU knows the car isn't moving.

Reason being is the H6 is very resistant to leaking at the heads under low power, as each cylinder is at a much lower power to that of the H4's. The above stall stress, or simply flooring it on the road, brings the pressure up and reveals the leak.

edit; here's actually a video I took of the engine prior to it being sent back, you can see how it's bubbling (and also spewed quite a bit of coolant out the funnel), while running pretty rough on idle;
https://1drv.ms/v/s!AvmNywYaxo2RnURisNso0m1pVO-D
(oh and sorry about the video orientation, my phone's gyro is bust so it doesn't know to rotate the video when recording...)
Paul17041993
 
Posts: 3
Joined: Fri Dec 13, 2019 11:41 am
Car: MY04 EZ30R outback gold premium

Re: 3.0R wrecker engine showing signs of blown heads...

Postby subyroo » Sun Dec 29, 2019 3:10 pm

Paul17041993 wrote:So in summary they've booked another engine replacement first thing in january, so we should hopefully be out of this scenario pretty soon.


Good to hear that they have accepted it as bad and are replacing it for you. :good:
I was expecting to read somewhere in that post that they were going to blame you somehow for the problem. :shock:
Pedro

2021 Honda HR-V VTi-S
MY03 XS Forester (owned for 13yrs.)
Man blames fate for other accidents but feels personally responsible for a hole in one.
User avatar
subyroo
 
Posts: 370
Joined: Thu Feb 05, 2009 7:30 pm
Location: Sunshine Coast
Car: 2021 Honda HRV VTi-S

Re: 3.0R wrecker engine showing signs of blown heads...

Postby jeb » Mon Jan 06, 2020 3:56 pm

My engine is good!

Looks like it needed a new radiator. We fitted a new koyorad unit. Now the overflow bottle syphon is back in action and engine temps are more stable and generally lower (87-92 on highway). Not sure what was wrong with the radiator. It held pressure, couldn't see gunk when flushed.

Honestly thought my head gaskets were toast. Glad that's sorted, now I put my efforts/funds into a lift, exhaust and tune :D
jeb
 
Posts: 2
Joined: Sat Dec 28, 2019 9:26 pm
Car: 2005 Ez30r Outback

Re: 3.0R wrecker engine showing signs of blown heads...

Postby Paul17041993 » Sun Jan 19, 2020 3:06 pm

Well, to update on this, we've made good progress. The warranty replacement engine seems to be working pretty well, no bubbling when hot and worked, great torque and power, temp guage hasn't shifted one hair above operational temp. It does however seem to run a little on the rough side at the lower RPM's, and did stall a couple times with in-gear testing, but I've got an OBDII plug on the way to have a deeper look at that issue, which I'm guessing is the fuel regulator or servo getting on the sticky side.

There is however a newer coolant issue I need to work out, where it seems like it's sucking in air when it gets cold at night, but the problem is I'm not sure where exactly...
Basically you can top it up and bleed it, there'll be no air in the system whatsoever. But over the course of a few days of casual driving, you'll start it up and hear a bit of sloshing in the heater core as air gets pushed out. So I guess I'm going to have to check the heater core for leaks...

EDIT; turns out the little hose to the 'manifold absolute pressure' sensor wasn't connected, surprised the ECU never complained about it, and silly me thinking that slight noise was the alternator...
Paul17041993
 
Posts: 3
Joined: Fri Dec 13, 2019 11:41 am
Car: MY04 EZ30R outback gold premium


Return to 3.0R & 3.6R engine specific

Who is online

Users browsing this forum: No registered users and 1 guest