Jump to content
Ultimate Subaru Message Board

Bubbles in overflow tank - HGs? Maybe not... Now with YouTube !!!


Recommended Posts

I just bought my '98 OBW and started driving it.

 

I took the over-flow tank off to clean it but didn't fill it with any water.

 

Checked it tonight for first time.

 

There was a bit of water in the bottom (I guess what came out of the rad) and it looked like it was burping.

 

I added water to the full hot level and when I did that, big bubbles came out of the tube every two seconds or so...

 

Is this exhaust gas bubbles or just air caught in the rad from the empty bottle?

 

I was expecting tiny bubbles with foam if it was a hg problem from what I've been reading here..

 

Hmmm..

 

Steve

Edited by samneric
Link to comment
Share on other sites

Is the radiator full or need some fill?

 

Doesn't sound good to me though.

 

How many miles?

 

210K miles.

 

Rad may need some fill because the overflow was empty. Will check again on the w/e and do the "Let it run with the cap off till the them opens thing".

 

This is not a big deal for me - I'm ready to do the HG's anyways.

 

Will make the car good for another 100K

 

Steve

Link to comment
Share on other sites

yep, sounds pretty severe. how long have you had the car?

 

I bought it in August but its been off the road while I "sealed" the transmission.

 

Just got it back on the road now to where I am starting to get used to it.

 

Last night I changed the knock sensor and exhaust gaskets - drives quiet and doesn't misfire now :) I like the power of the engine - very nippy. Car rides very smooth - way better than my Brat.

 

So to drive it until I save the money for the HG job - put the subaru water conditioner in and keep re-filling the water every weekend???

 

Steve

Link to comment
Share on other sites

Try the K&W block sealar, the nano-tech version in the green bottle. Flush the system and apply using clean water.

 

Thank you! Will hunt it down...

 

Also... with the comment about this being severe....

 

I obviously don't know if it has been driven overheated....

 

If it has I can assume the heads need to be re-surfaced.... Does the block ever need re-surfacing??? :eek:

 

I have read about the main bearings getting damaged if the oil wasn't changed on an overheat.... Are there tell tail signs that I will need to split the block and look at them also???!

 

Kind of exciting but scary at the same time ...

 

Steve

Link to comment
Share on other sites

Thank you! Will hunt it down...

 

Also... with the comment about this being severe....

 

I obviously don't know if it has been driven overheated....

 

If it has I can assume the heads need to be re-surfaced.... Does the block ever need re-surfacing??? :eek:

 

I have read about the main bearings getting damaged if the oil wasn't changed on an overheat.... Are there tell tail signs that I will need to split the block and look at them also???!

Steve

 

i think you would have to have the oil checked out to really know, unless there is metal stuff in it.

 

heads should go to the machine shop to be check, and surfaced if needed. i was quoted 20$ per to be cleaned and checked, 47$ per to be surfaced.

 

if the engine is running well now the block should be ok. and probably not worth it to have it done any way. not price wise so much but way easier for a 2.2L swap. same reason regarding splitting the block. it can be done but 2.2s are cheap.

 

if you wanted a good 2.5L engine, to rebuild top half, i would look for one with a busted timing belt. repair and reseal and then you are good to go. not a garrantee against previous overheating but at least it isn't being sold because of it.

Edited by johnceggleston
Link to comment
Share on other sites

i think you would have to have the oil checked out to really know, unless there is metal stuff in it.

 

OK, just did some reading on another forum - so I am looking for low oil pressure? It was stated that bad bearings can cause low oil pressure - even if they don't make noise.....

 

Or are you talking about the oil colour and consistency?? In which case what would these symptoms mean?? Thin oil, black oil etc.....

 

Steve

Link to comment
Share on other sites

Oil pressure reading is taken directly off the pump so it's mostly the pump that is responsible for the pressure - not the bearings. Bad bearings will not show any difference in oil pressure.

 

If you are willing to do it - go ahead and split the block and replace the mains and rod bearings. An EJ22 swap might be cheaper but you don't get that 165 HP for free! IMO losing 30 HP isn't real desireable either so you have to weight your options - a bit more labor and parts to do the bearings vs. saving money, losing HP, and devalueing the car (not a lot of people will want to buy an engine swapped OB on the open market).

 

The heads will run about $450 to $500 for a full rebuild - valves, guides, stem seals, resurface, clean, etc. You are looking at about $400 in parts for head gaskets/timing belt/water pump/seals/hoses, etc. The main and rod bearings and possibly crank machine work will add to that. I would figure at least $1500 in parts and machine work.

 

GD

Link to comment
Share on other sites

figure at least $1500 in parts and machine work.

 

GD

 

:eek:

 

Wait... Let me say that again...

 

:eek::eek:

 

:)

 

Thanks for the info - good advice...

 

I do want to keep the 2.5 - I really do like the torque and performance. Driving at 35 in fifth is neat.

 

Luckily, I only paid 2000 for the car so I still should come up less than the 4400 that it is listed for in the blue book.... That's with a new clutch, tranny and engine reseal... oh and new rotors and pads.... and knock sensor... the list goes on :)

 

Steve

Link to comment
Share on other sites

Yeah - with a full rebuild - splitting the block and all - you can expect another 250k out of it easily. If you go with synthetic you possibly get to 350k+

 

Basically a new car at that point. Most of the hard stuff will be done by the machine shop you use - all you have to do is dissasemble and reassemble. Simple!

 

Buy a cheap engine stand. Worth the $35.

 

GD

Link to comment
Share on other sites

You don't mention any overheating? Blown headgasket Phase I EJ25's usually overheat when the gaskets blow.

 

Additives are usually discouraged on your engine, it's the later Phase II EJ25's with a different failure mode that the additive is used in.

 

I wouldn't go the JDM route. Top dollar due to high demand for another used, decade+ old engine with low percentage original headgaskets. It's not a terrible deal if you replace the gaskets first.....but in that case I have a 80,000 mile EJ25 you can have for the same price. :lol:

 

Given you have the ability and seem confident a full on rebuild or just a head gasket job are both great options. The knocking usually gives you ample time to prepare for a rebuild if you need it. And there's a good chance you never will.

 

Chances of it hosing you are small, but occasionally they do send a rod through the block, helping a friend with one of those in his OBW right now. So if you do the rebuild you're paying a lot for a little insurance which isn't always bad given the situation, skills, what's a good fit for you.

Link to comment
Share on other sites

You don't mention any overheating? Blown headgasket Phase I EJ25's usually overheat when the gaskets blow.

 

I have only been driving it for two weeks and I only drive about 20 miles each way to and from work so maybe it hasn't had chance to overheat yet?

 

I did drive it back from SC (800 miles???) and it didn't overheat.

 

As soon as I got back I checked the rad (which was full of clean green coolant) and the overflow bottle. The bottle actually had black oil sitting on the surface of the water :eek:. You could put your finger in and pull it out as if you were dipping it in engine oil. - Still the rad had clean water in it so I just assumed someone had filled the overflow bottle with oil and I took it off and cleaned it (that's why there was no water in it when I first started driving it two weeks ago).

 

Very strange circumstances indeed - the plot thickens :)

 

Can you keep the 80K engine on stand-by? :grin:

 

Steve

Link to comment
Share on other sites

Right, like GD said there's no question what the issue is, but it may have an underlying cause and I'm curious how much it was driven while overheating by the previous owner.

 

You don't still have contact with the previous owner do you?

 

Unforch not. It was sold by a dealer and from all the paperwork he gave me, the car changed hands a number of times before he sold it on ebay - now we know why !!!!

 

So left with the dilema - do I just do the HG's (presumably at least getting the HG's checked for plumb) or do I fear the worst and go for bearing replacement.

 

Prob going to take my chances with the HGs - $500 job. Would like a more secure feeling though - which is why I was looking at a JDM block with my resurfaced heads put back on.

 

What is the first symptom of main bearing failure - knocking? It does make a louder noise for a few seconds when first starting - maybe piston slap???

 

Maybe I should take a video from cold of it starting with sound...

 

Just want the best stab at this before putting too much money in a certain direction that may proove wrong.

 

Steve

Link to comment
Share on other sites

like i said earlier, they usually start knocking and give enough warning to plan a repair. but they can let loose, far less often though.

 

definitely diagnose the current noise and make sure what it is, though you sound confident it's not rod knock? replacing head gaskets on an engine already knocking would be frustrating.

 

tough dilemma, there's just no way to know what's up with it for certain.

Link to comment
Share on other sites

definitely diagnose the current noise and make sure what it is, though you sound confident it's not rod knock? replacing head gaskets on an engine already knocking would be frustrating.

 

The current noise doesn't seem like a knock - just louder on startup - I will get the video done tomorrow morning when it is cold.

 

I agree about a loud knock giving me advance notice so I'll prob end up taking my chances with the current block.

 

Steve

Link to comment
Share on other sites

I haven't listened to it yet (no sound on this machine), but rod knocks tend to change under load - they will get louder under load, and then when you let off the hammer you get a "decel knock" that changes pitch as the loose rod slaps the crank in a different way..... a startup noise on the EJ25D's is typically piston slap - which is a tiny bit annying but not in any way detrimental. Most of them have it to one degree or another and it doesn't seem to affect them lasting 300k+ just like any other Subaru engine. Rod knocks get *louder* as the engine warms due to the oil thinning out to it's proper SAE viscocity. If the noise goes away (or just gets quieter) with increased engine temp then it's either valve train noise (on hydro lifter engines which your's is not), piston slap, or an accesory item like a t-belt idler, alternator bearing, AC idler, etc.

 

GD

Edited by GeneralDisorder
Link to comment
Share on other sites

If the noise goes away (or just gets quieter) with increased engine temp then it's either valve train noise (on hydro lifter engines which your's is not), piston slap, or an accesory item like a t-belt idler, alternator bearing, AC idler, etc.

 

GD

 

Phew, thats somewhat of a relief!!!

 

So if I change the oil and there is no shavings in there then I am somewhat safe to go ahead and just have the headwork done and stick new gaskets/belt/idlers etc on there.

 

Steve

Link to comment
Share on other sites

If you find anything in the oil itself then toss the motor in the dumpster :rolleyes:. If you really want to look for shavings you need to cut open the oil filter, stretch out the element, and look in the deepest part of the corrugations for metal. Typically I use a clean magnet and then wipe it off onto a white paper towel and inspect closely.

 

Getting the oil filter apart without *creating* a bunch of metal shavings..... I'll leave that up to your imagination.

 

GD

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...