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Old 03-23-2020, 07:31 AM   #1
Scooby Newbie
Member#: 512533
Join Date: Mar 2020
Default EJ22 Swap Overheating Log

(Possibly solved in most recent entry below!)

-----Old entries------
I'm posting here so that everyone may learn from my experience as I go though this process. I have a detailed log that you can read below as it is very extensive. I will update this post as events evolve.

Tl;dr- Engine runs smooth mostly but overheats after hill climbs. Headgaskets, radiator, radiator cap, thermostat, oil pump verified good although headgaskets not fully tested but obvious bad signs are not present (listed below). Possible water pump issue and coolant flow issue. Unsure of air bubbles in system. Will check water pump and burp coolant flow soon.

Feel free to reply if you have any suggestions as I am still learning about EJ series engines.

======EJ18 N/A to EJ22E N/A swap======

!!!!!(List of new and reused parts listed at bottom)!!!!!

===Over heating issue log:

Oil (75 miles) was changed due to break in oil dirty metallic dust from rebuild
Showed signs of some overheat.
no milky signs in oil.
no stress testing attempted.

(5pm to 7pm dry to drizzling conditions)
Drove on to highway @70-75mph
Drove 3-4 minute uphill @3k-4k rpm @60-70mph, possible abnormal vibrations felt via gas pedal (maybe just never noticed it before).
Noticed slight temperature increase above normal and exited.
At stop engine temp immediately increased to top range "H".
Car began to cool down after take off.
Turned into residential area to inspect while car is on
--noticed overflow was full
Drove toward home observing heat fluctuations. Used back roads and pulled over after 2 miles and noticed radiator cap cool to touch and added water.
Ported at home and idled to observe heat readings.
Top hose very hot and bottom hose only slightly.
Changed radiator cap and refilled coolant with no burping with normal engine temperatures.
Took same up hill route and about the same area and began overheating after hill climb.
Radiator observed to have two hairline fractures and spewed coolant in engine bay
Attempts to drive home unsuccessful due to constant over heating (less than a mile on residential roads).
Car was towed.

Radiator was replaced and was topped off with attempt at burping but not verified successful (coke bottle method).
--Cabin heater was turned on to full blast and was hot
--no observable bubbles after radiator fan turned on (not sure if this sufficed)
Test drove on highway and uphill course and noticed 3/4 hot on temp gauge
Returned to home.
While idled observed temps (with laser temp gun) of 187f-218f on block 140f-170f at radiator hoses.
Top hose very hot and bottom hose only slightly.
Throttle valve hoses hot.
Subtle audible loping noises while at idle with hood up but unable to determine origin (maybe crankshaft).

(3pm rainy conditions)
Subtle loping noises persist while at idle with hood up.
Thermostat changed with known good part.
Coolant added with no attempt to burp but full blast cabin heat observed.
Cold start and warm up temp 180f.
Test drove with OBD2 and observed coolant temp ranges 180f-208f during normal level driving @70-75 mph and semi-hard driving with prolonged uphills @3k-4k sustained for climbs of 30 mph of 3 to 4 minutes and 65 mph of 3 to 4 minutes, possible abnormal vibrations felt via gas pedal.
Engine mostly at 188f-195f during drive session with slight increase of 200+ at stops.
!!!when at complete stop/idle at home observed 230f (engine promptly shut off) boilover tank is full radiator cap cool to touch.
--perhaps due to loss of coolant during drive
--previous loping noises not found???

Will remove thermostat to verify if thermostat, throttle body or heater core has possible air bubble issue.
Will fill from top hose and radiator at an incline.
If issues persist then engine removal will be ordered.

=====Stress test results through out testing=====
No coolant leaks other than overflow
No visible headgasket leak indications:
--No bubbling in radiator at cold start
--No milky oil
--No obvious white smoke but will do further investigation
--No further HG tests have been attempted such as carbon monoxide/coolant contamination test, exhaust smell/coolant smell tests.
Top and Bottom hoses and throttle body hoses do feel hot/warm to touch which confirms thermometer is good (but perhaps does not stay open long enough although idle rpm does decrease when at operating temp).
Fans do work (temp sensor if EJ18/EJ22 apparently the same).
Overheats when idled after 30+ mins of driving.
verified hot air through climate controls.
*Have not verified if engine was burped correctly via heater core or throttle body due to repeated over flow.
*will attempt to stress test without thermostat and proper burp.

=====Attempts at fixing issue:
-thermostat replace
-burping (unverified if done properly)
-radiator cap replace
-radiator replace

=====Possible issues
-Crank shaft/bearings
-Headgasket (because subaru)
-water pump (was inspected, blades were good and 1:1 movement with no play, observed coolant flow in radiator)
-air bubbles in heater core or throttle body (will do inclined coolant refilling technique)

******Technicians note******
Engine did exhibit some minor overheating upon purchase. Did not notice any warpage when engine was torn down for inspection and refurbishment
Original owner did not seem the type of person knowledgeable of possible engine issues. Engine may have experienced warpage or other internal block damage at some point.
When disassembled the cylinder bore did not show any warpage and other signs of abnormality and had consistent bore hatching and piston rings seated correctly.
Pistons did not show any abnormal scratches or wear besides one rod knock which did not persist after installing.
Plastic oil separator plate was very loose and was promptly replaced with metal one.

EJ18 (fully functional and no overheating issues) > EJ22 (currently partial rebuild)

=====Kept from EJ18:
Engine bay wiring
--Spark plug ignition pack
--Coolant sensor plugs
--MAF wiring and sensors
--All timing sensor plugs
Intake manifold
Coolant Crossover pipe and sensors
Engine Mounts
MAF and tubing
A/C compressor bracket
Power Steering pump
O2 sensors (positions differ but should be non-issue)

=====Transferred from EJ22:
Heads (single port exhaust)
--Stock head internals (appeared to be in good condition)
Single port exhaust
--Stock Pistons and Rods (sign of rod knock but no knocks have occured after rebuild, no scratches, appear to be in good condition)
--Stock Rod bearings and crank shaft bearings (appear to be in good condition, no abnormal wear)
--Stock Rods (good condition)
--Stock wrist pin (good condition)
***noticed no play in rod while installed on crankshaft
***noticed calcium buildup in water ways
Water pump
Coolant lines
All pulley bearings
Main Belt pulley and sprocket
All sensors (including timing and sprocket)

=====What's new:
Metal oil separator plate
Piston rings ("turbo rings")
Valve cover gaskets
Oil Pump
-Radiatorcap (13psi)
Thermostat*** (tested good)
Recent oil and oil filter change due to new piston rings
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Last edited by BluShopnCart; 05-22-2020 at 10:55 PM.
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Old 03-23-2020, 09:49 PM   #2
Scooby Newbie
Member#: 512533
Join Date: Mar 2020

(4pm-6pm dry conditions)

Loping sound found to be belt rubbing against belt cover

Removed thermostat and turned main crank pulley and verified blades in water pump move (blades were in good condition with no wear or abnormalities when inspected)
Removed thermostat induced coolant leak and placed only the thermostat gasket. started cold engine and attempted to fill but noticed rapid air bubbles consistent with headgasket failure. Unable to determine if it was due to air seeping through due to poor seal with thermostat missing.
Replaced thermostat and started engine no rapid bubbling found. Heat on full blast no A/C active. Topped off coolant observing burp bubbles and continued filling through out refill process. Monitored engine temps of 187f-188f (OBD2) and hose temps of 150f-160f (laser temp gun).
Massaged hoses at Throttle body and heater core lines seeing water level change at radiator and some small bubbles. Noticed top heater core line slightly hotter than bottom. @188f-190f thermostat did not open and fan did not turn on and bottom radiator hose only warm.
Continued to massage hoses and turned on A/C and reduced temp but only due to A/C fan not coolant temp.
Applied consistent RPM of 2.5k and reached 201f-203f and observed temp drop to 190f-193f and coolant flow before topping off and seeing swriling of coolant. Lower rad hose hot and heater core lines equally hot. No bubbling of any kind.
Closed cap and test drove on hwy @3.5k rpm @75mph coolant temp of 194f consistent. At stops with slight increases but no overheating. Returned home at 6pm and kept rpms @2.5 to induce 201f-203f and observed drop to 190f-193f. Turned on A/C fans to cool even further. Overflow full but probably due to filling

Test results:
Thermostat works but only at 200F- not sure if this is the right rating as it says 78C (172F). Maybe contracts slightly during 180-190 range but not enough to prevent major overheating.
Fan does kick on at 200+F but A/C are more effective
Heater core and Throttle body seem to be fully flushed
Burping may have been successful but will try again
Hoses and cap did hold pressure and water did flow
No signs of headgasket failure

Technicians note:
I think my car is a big baby and just doesn't like uphills and does completely fine on flat streets otherwise it will boil over and overheat afterwards. Either that or the Thermostat and fan aren't working on soon enough and stop too early. Perhaps Thermostat and Fan sensor is not the right rating. Maybe my EJ22 block with turbo piston rings is too high of compression on uphills and the cooling system can't compensate for the heat it generates which would mean I would have to put in a better performance radiator and fan or just rebuild with more appropriate rings. Also these new rings may still be going through the break in period and this is still on the second oil after the initial oil change for break in. I yet to have reach 500 miles of the recommended break in period.

Next step:
More research on normal coolant temps.
Test on uphill climb and immediate rest to gather data.

Last edited by BluShopnCart; 03-23-2020 at 11:40 PM.
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Old 04-13-2020, 07:03 AM   #3
Scooby Newbie
Member#: 512533
Join Date: Mar 2020

(3am-4am dry/drizzle conditions)

Have not touched it since the last test period other than checking the pulleys for the loping sound.

Drove it up a smaller grade averaging 2k-3k rpms to keep overheating at a minimum.
Observed temperatures around 188-192 with 201 highs but cooled down with nothing higher than. Will try again on the more strenuous hill climb. Have not noticed anything out of the ordinary.
Seems as though the original overheating issue may have been due to an air bubble. I will check fluids again.
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Old 05-22-2020, 10:54 PM   #4
Scooby Newbie
Member#: 512533
Join Date: Mar 2020

EJ18 to EJ22 overheating possibly solved

I may have figured it out for the most part.

The coolant was not getting to the "active" side of the thermostat at a good enough flow. There is two paths of the coolant, one coming from the throttle body and one from the heater core. the throttle body coolant line did get hot but would not deliver enough coolant to open the thermostat. (This was immediately after burping the system).

I let the engine get to over temp (200-208) and then would set the fan to heat with no A/C to '1' and would get hardly any cooling even though the fan would kick on at 203. But I then set the fan to '4' and at 203 would immediately see cooling back down to 186! Success. I have deduced that the active side of the thermostat wasn't getting enough coolant therefore I must burp or use a bypass to flow more coolant.

Solution 1: Remove the heater core coolant lines and buy a hose to reroute the coolant back to the pipe leading to the thermostat

Solution 2: Create a bypass consisting of two 5/8 t-fittings and one hose and cut the heater core lines and place it in the middle to allow coolant to flow to the pipe and heater core.

Solution 3: Try burping it again but on an incline rather than just using the special coolant funnel.

This may also lead to more questions about my engine like "is my heater core creating an air bubble not allowing coolant flow" or "is the coolant flow made for an EJ18 compatible with an EJ22".

Updates to come.

Last edited by BluShopnCart; 05-23-2020 at 12:16 AM.
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Old 05-23-2020, 01:19 PM   #5
Scooby Newbie
Member#: 512533
Join Date: Mar 2020


Noticed a good amount of fluid was missing upon first inspection. Set car on my incline and used overflow funnel. Some bubbling occurred from initial refill. started car and got up to temp. Rev'd to 2k and watched some bubbles come up. Set heater temp to full and fans to full. watched temp go from 206 with gauge indicating to overtemp and then decreased to 192 noting some minor bubbles. Tried it again then 204.8 and down to 192 and then again from 203 to 192. Turned off heater and fans and saw 203 and down to 192. Turned heater to cold thereby closing the heater valve (if such does exist) and observed 203 and down to 192. When car is idle and at full stop it will go 203 and down to 192.

Before at idle the engine would overtemp and go to 208+ but now that seems to have been resolved by conducting the incline filling technique and letting the valve open at least 3 times. the final test will be a prolonged hill climb.
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