My 1994 Volvo 940T wagon with 176k miles questions re replacing head gasket.

[940T Wagon 1993 & 1994]

I recommend you buy the crank holder tool. You are also going to need a large breaker bar, a 24mm socket, and possibly a pipe to slide over the breaker bar in order to get that crank bolt off and back on tight.

There have been reports that aftermarket cam and crankshaft seals are leaking soon after installation. You want to buy the highest quality seals that you can for the job.

There have also been reports the blue box OEM Volvo stuff for these cars can be cheap aftermarket parts put in a blue box and marked up.

Make sure to get the round tooth timing belt for that year. Older years are square tooth.

I would do all the cam, crank, aux shaft seals and a new high quality water pump while in there. It is much easier to install a water pump with the head off and get the upper seal compressed well.

Plan on needing to do PCV hoses, vac hoses, wiring repair, heater hoses, gaskets, belts, and probably all the bushings on the accessories too. Don't put those blue URO bushings in there. They will turn to dust in a year.

Who makes the best seal kits? Elring? Mahle? Victor Rinz? Who makes the best water pumps and radiators?

 

[940T Wagon 1993 & 1994]

Who makes the best seal kits? Elring? Mahle? Victor Rinz? Who makes the best water pumps and radiators?

What are the accessory bushings?

 

[940T Wagon 1993 & 1994]

Who makes the best seal kits? Elring? Mahle? Victor Rinz? Who makes the best water pumps and radiators?

I thought I had square tooth timing belt on a 1994

 

[j.pelchat]

Will definitely need a large Breaker bar and pipe to R&R the head bolts. Get an impact 14MM socket. I second on the crank holder; it also helps remove the cam sprocket

 

[ZVOLV]

google -----------site:turbobricks.com "enter search term"

You can also edit posts instead of double reply. It keeps thread length down and makes it easier to read.

 

[NLRegina]

What are the accessory bushings?

The rubber bushings that your alternator and AC compressor bolt to on the accessory bracket on the right side of your engine

I thought I had square tooth timing belt on a 1994

1993 and up should all be round tooth unless something was swapped over. Round tooth lasts longer and is quieter, it's an upgrade in every way

 

[940T Wagon 1993 & 1994]

5/22/26 I made some progress tword removing the valve head..all belts are off engine, I do indeed have round edge timing belt gears , in TDC 0 degree at cam gear and harmonic pully, intake and exaust stud bolts all removed. Where i'm stuck is 4 bolts where exaust manifold bolts to stock turbo...1 of the bolts doesnt have enough clearance to get the closed end of a box wrench in. When I try loosen with 13mm box end I can tell it will strip the bolt. So looks to me like I have to disconnect the 3 bolts from exaust end of turbo to manifold and take the turbo out as well to get to the 4th bolt at manifold/turbo?
Or I can try to buy a narrower 13mm box wrench to be able to access the nut in this narrow spot. Any other ideas?


I did not know/realize that there is a seperate manifold to block bracket. I will check that it is there and doing it's job. I see it on a part diagram, will look for it in person.

 

[NLRegina]

Maybe a crows foot wrench would work better? Maybe you can try and leave the manifold where it is and just pry it off to the side a little bit. That works on NA cars but maybe there's not enough clearance for that on turbo cars.

 

[ZVOLV]

Just pull the manifold with the turbo. That is what I am doing right now.

Then you want to make sure your manifold to block bracket is there and doing its job on reinstallation.

 

[ZVOLV]

I may just pull the head and the exhaust manifold together.

I have always bent the spark plug wire shields out of the way with a hammer to remove the bottom bolts, but I want to be nice to my parts now that I can't get them anymore.

 

[ZVOLV]

I pulled the 15G and will be installing a 16T center cartridge and cold side. FWD turbos will only fit FWD turbine housings BTW. Conical housing was only from 1994? to 1995 850 Turbo and then it went to flat flange, and then angled flange. I have a conical housing from a 1995? 850 Turbo.

Get yourself some OEM turbo return gaskets, new crush washers for oil feed and coolant pipes, new oil return o rings. Replace those two soggy oil cooler hoses, get new hushers, set valve lash first.

Fix all oil, coolant, and air leaks.

Replace all soggy bushings for the alt and compressor. New belts, New NGK6BPRES plugs, Bougicord wires, Bosch dist cap.

New timing belt, front end seals, and high-quality tensioner pulley/

You also want to support the downpipe to the bellhousing (like on my 1991) or to the transmission, like yours should.

 

[ZVOLV]

I just heaved the head out of the engine bay. I got stuck on something and I couldn't figure it out. I had to let the head down and almost scratched it against the block. Luckily the head gasket stuck to the head and protected it.

I plan on always removing the exhaust manifold/turbo before pulling the head now.

I was getting stuck on the turbo oil feed line. I got it off, but my back got a little bit tweaked. It wasn't worth the shortcut attempt.

 

[940T Wagon 1993 & 1994]

I am almost there, 1 more bolt of the 3 on turbo to manifold, need to remove turbo, then I'm ready for cam removal, head bolt removal. I'm going to order an IPD turbo cam and all parts you recommend. I am going to order new head bolts, do88 coolant hoses, Elring head gasket, valve cover and engine seal kit, hushers, bushings for A/C Alternator mount, new Continentinal timing belt (round teeth), new tensioner spring and assembly, new NGK plugs, wires, I have a new Bosch rotor and cap. Vacum hoses are trashed and must be replaced, new OEM water pump, Nissens radiator (32 year old radiator was leaking and caused overheating, will clean oil seperator and throttle body, 2 grounds to engine need brushed at body and engine connection, new crush seals and o ring for turbo as you recommend, all hose clamps are in bad shape, need to check and replace PCV, flame trap. Washers on exaust manifold need replaced (corroded) need new exaust and intake head studs, new thermostat 87°, new temp sensor, new nuts for intake and exaust, new belts, belts were setup with only one belt running water pump pully but the water pump has places for 2 belts. Shouldn't there be 2 belts driving the water pump for proper safe operation? Got an electronic Kobalt brand torque gauge with range from 19.8- 99 ft pounds with better that 1% accuracy certifcation. Going to notch grooves in old head bolt to carefully clean head threads, then brake cleaner and blow with compressed air and lightly brush apply 10-30 motor oil to threads and under bolt head prior to reassembly. Will take valve head to a very good machine shop for checking head for flatness (I will check block flatness must be within .002" I think). Head will be blasted clean regrind surface, check valve seats, valves, machine same, replace guides. Engine is original 32 year old, 176k miles. I'm thinking new valve springs and assembly are a good idea or is it better to have spings checked and replaced only as needed?

When head is off Im hoping I can see the symptoms of a blown head gasket and that the problem is NOT a cracked block but the problem happend when overheating and I had the hood up and I thought I could hear a suttle noise that was the gasket blowing...then the engine did some rock and roll as the coolamt got into the engine.

 

[ZVOLV]

I recommend that you install the water pump before you install the cylinder head. It is easier than trying to shove the pump upwards and getting the bolts to line up with the holes once the head is installed. You are trying to compress that upper ring and lining up the bolt holes at the same time. I paid $30 for an OEM Volvo Penta water pump upper seal. I don't recall having problems there in the past with the aftermarket stuff, but sure enough, when I did a pressure test I was able to get it to leak right there from my aftermarket seal I installed about 20k/5 years ago during the last HG swap. There are reports that the aftermarket rings are not thick enough and easily start to leak.

I also found a leaking heater valve and the hoses were about to let go. I didn't see heater hose valve on your list.

I found my thermostat housing gasket leaking. Add that to your list.

What bushings did you buy for accessories? Don't use those blue URO ones. They turn to dust in about a year. I may try some Yoshifab solid bushings. I have some $45/each OEM bushings but I may save those for another day.

You want NGK copper plugs, Bosch cap and rotor, and Bougicord wires. My Bougicord wires were actually tired and pulled off the plugs too easily. The front plug also had the screw-on tip backed off the top of the plug. I think I need to buy new wires.

After decades of hoarding gaskets, seals, and washers I actually have almost everything I need "in stock". I am going to do new timing belt, new tensioner, and leave the cam/crank seals alone if they are not leaking.

I have piles of copper washers that I have bought over the years.

I have replacement upper and lower hoses, but I need replacement hose clamps due to corrosion. I am going to try the spring clamp hose clamps this time. I don't like worm drive clamps. They are easy to overtighten. I had a couple hoses mushrooming out from overtightened worm drive clamps. The spring type clamps also hold constant tension on the hose as the hose thins out over the years.

The thermostat housing is corroded too. I may buy the $18 aftermarket one.

I am going to reseal the oil cooler. That is actually what started this whole job and I just went down a rabbit hole of tearing it all down. I have a $12 OEM PCV "S" hose to replace the $1.50 cracked one that was causing everything on under the intake to get greasy. Hopefully this one lasts longer.

The soggy pre-1987 solid engine mounts are getting replaced by some Yoshifab mounts.

On your 1993 Turbo you will have two coolant hoses going to the oil cooler. They commonly get soggy from oil leaking onto them from above, and can burst and cause an overheat. Plan on commonly replacing those two hoses as maintenance. The seal for the oil cooled sammich plate is different than the water cooled one. Make sure you get the right one.

I also plan on replacing as many vacuum lines as possible and installing clamps on each hose to reduce the chance of them leaking. I have a pile of the little green spring clamps that were on the hoses from the factory. Fewer tiny air leaks=more power and fuel economy.

An IPD cam is in my head already. I shimmed it and installed OEM hushers probably around 2022. I plan on measuring what I have for clearances on the bench, or once I mount the head.

I also need to replace all the exhaust hardware. It is cheap insurance because you don't ever want a stud to break off in the head. On my 240 B230FT swap there are a couple studs busted off in the head that I need to deal with. I also try to use the "OEM" stuff here too. I don't know if the cheap studs are any good.

I have chipped computers, 16T turbo, IPD sways, and the old school Cherry Turbo upper and lower chassis braces going in too. I am tired of looking at them sitting in the garage.

 

[940T Wagon 1993 & 1994]

Roger re oil cooler hoses, mine feel super mushy, will replace. Not replacing heater hoses now because my heater core needs to be replaced and setup now bypasses the core with no heater hoses, I put a T fitting in its place. Will need to fix heater core b4 winter. Good Idea re motor mounts. Where do I get Yoshifab? I did not understand what you said about the oil cooler part for the sandwich?

 

[940T Wagon 1993 & 1994]

Roger re oil cooler hoses, mine feel super mushy, will replace. Not replacing heater hoses now because my heater core needs to be replaced and setup now bypasses the core with no heater hoses, I put a T fitting in its place. Will need to fix heater core b4 winter. Good Idea re motor mounts. Where do I get Yoshifab? I did not understand what you said about the oil cooler part for the sandwich plate, make sure I get the right part? Pressure tester for coolant system is a very good idea...I will pick up a good one. So it is OK to just have a single belt that drives the water pump pully I guess per your picture.

 

[ZVOLV]

I have the air cooled setup pictured up top. You have the water cooled setup pictured below. 1992 is the changeover when they went to the bigger radiator and the electric fan.


Seal number 4 and seal number 5 are not the same part from what I understand. I was just warning you that you may order the wrong one. I think the #5 is a seal with square shoulders. Many places may sell you a black round shoulder seal (like a regular o-ring shaped). I will take pics of what I mean when I get in there.

 

[ZVOLV]

I haven't ever tried these solid accessory bushings, but I may give them a go.

Yoshifab

Volvo performance and fabrication

yoshifab.com

Single belt is the way it is supposed to be on your car and mine. I have seen 240 with dual belts with the alternator mounted down in the bottom right, where the power steering pump is on a 7/9. There are even different diameter water pump pulleys from what I have read, but that is for another thread.

I need to do the heater core on this 1991 740 too. Mine is bypassed, but for some reason I left the heater valve on there. I am gonna take it out and loop a hose from the pipe to the head.

 

[940T Wagon 1993 & 1994]

Thank you for the parts diagram! Where can I find those parts diagrams? Now I understand. I think I might need to have the car in the air to access and install the oil coolant hoses and the gasket. Yes Yoshifab bushings and motor mounts look like a good idea, Thanks!!! I will send a picture of where I'm at now. I thought my camshaft looked suprisingly low in wear and the camshaft area clean for 176k miles, camshaft retainers and nuts have a beautiful copper/gold coating appearance. I ran Valvoline 50% oil/synthetic for years the switched to Mobil 1 full synthetic last 90k miles? Only see the slight wear at top of cam lobes, rest of cam surface super smooth and free of wear.

 

[ZVOLV]

Those diagrams are from VIDA dealer software.

I keep going deeper into ripping my engine bay apart. I may lift the engine and take care of an oil pan gasket leak and install two OEM oil pump pickup tubes while I am in there.