replacing my head gasket - Honda Prelude Forum

89PreludeSi · 07-29-2002, 11:38 PM

heres my problem... i need some advise for anyone that can give it, my oil is somehow getting into my coolant, i flushed my coolant completely, it was nice clean green i then went for a drive for about 30 mins... and it was fully white, which means my coolant is mixing with oil, and im losing oil to my radiator, i dont believe i am burning oil or coolant, its simply boiling over when the engine gets really hot, so my question is, if my head gasket is gone, what is involved in the replacement, i have to install a header this weekend, so if i have the whole day, should i just pop off the head and check for warping, and if its straight just replace the gasket? or is it way more involved then that? if it is, id like to have it sent off and milled... just for the extra compression... im gonna stop ranting now and let you guys tell me what you think... thank you, oh so much

hondaprelude88 · 07-29-2002, 11:40 PM

Definetly sounds like a blown head gasket.

RedRacerX · 07-30-2002, 12:09 AM

Heck yea it does.

that not good man, Need to get a B20A5 Or JDM B20 lot less oil Problems.

89PreludeSi · 07-30-2002, 12:14 AM

i have b20a5...... i bought the car about 3 weeks ago.. never thought to check color of coolant..... but yeah... make the best of it right?... how much should i get milled off the head

..... and what else performance wise can i do? oh yeah... other than removing intake/exhaust manifold what is involved in removing the head? oh yeah... the car only costed me 2500$ us.. and its got 4ws... and fully loaded ... so i got a good deal, i knew it had problems when i bought it, just didnt realize the head was gonna need work... what if i get the head off and theres no sign of cracking or cracks in the head gasket?

TheCecil · 07-30-2002, 09:46 AM

removing the head is not really easy. it can be done, but it will take a while to do it. you have to pretty much disconnect everything from the head. the intake and exhaust maniflds, valve cove, cam gears, cams, cyl sensor, distributor, timing belt, powerstering pump, and alternator. there are 10 bolts ataching the head to the block. they are torqued 49ft/lbs so they are really in there. just take those bolts out, remove the head, put a new gasket on, put it back together, and u r done. i got all this info fromn the factory service manual. if u have any other questions, ask me.

Mathrin · 07-30-2002, 05:47 PM

You actually dont' have to take the intake and exhaust manifolds off to remove the heads. There is 50 steps to the removal and instalation of the head according to Chiltons. I'll be glad to outline the process for you if you like.

89PreludeSi · 07-30-2002, 06:43 PM

i have the haynes manual.. and they only tell you how to do it when the engine is out of the car and stipped down... but yeah... time is not really an issue... i have til sept..... so if that give you any idea of my timeframe... althought id rather do it over a weekend... disassamble one day, get it milled, put back together.... by the way.. this is a long weekend... lol... if the head is straight... i wont get it milled.... i just dont like white coolant... its scary.... like i said... im putting a header on.. so ill have the ps pump, alternator and CC out... as well as header... so it shouldnt be that far off.... i plan to add a turbo so would a thicker gasket be better? i just change something so i can get something out of this whole ordeal.....thanks for listening

Mathrin · 07-30-2002, 06:58 PM

You won't need an week end. You an do the whole thing in an afternoon. Everything can be reached from the top of then engine with the exception of the timing belt. If you have car up on blocks then you can reach it from below real easy.

If I get around to it, I'll put the complete remove/install as listed from Chiltons. Then you can just use the one you find easier.

Preyluder · 07-30-2002, 07:37 PM

Removal of the head is not an easy procedure. I've done it twice, but that was with the help of my mechanic. You need to replace your gasket soon, otherwise other problems could occur.

Mathrin · 07-30-2002, 08:19 PM

Preyluder is right. I wouldn't even drive the car if you might have a bad head or head gasket.

As for it being easy, I think it is. Tedious though. A lot of nick picky things, but if your through then its no sweat. Its easy to forget something if your not careful.

89PreludeSi · 07-30-2002, 10:03 PM

well, ive kinda started prepping for it..... i removed my AC, and cruise control.... those are 2 things i wont have to worry about... i plan to do it all this weekend...... im most likely just gonna keep the head stock, because if i go for high compression i wont really be able to turbo it, so ill just give it a good cleaning..... my last question is.... if i get a grinder with a buffing/cleaning wheel.. could i P&P my own head? and how about harder valve springs... do you have to remove the valve train to do any of this?

Mathrin · 08-03-2002, 05:19 PM

The cylinder head temperature must be below 100 F (38 C); allow the engine to cool for several hours if the car has been recently driven. Turn the crankshaft pulley so that the number one piston is at Top Dead Center (TDC) of the compression stroke.

1. Disconnect the battery ground cable.
2. Drain the cooling system.
3. Remove the air cleaner and intake duct assembly.
4. Label and remove the brake booster, PCV and charcoal canister vacuum hoses from the intake manifold.
5. Remove the engine ground cable from the cylinder head or valve cover.
6. Relieve the fuel pressure using the proper prodecure. Disconnect the fuel lines.
7. Disconnect the accelerator cable at the throttle body or carburetor. On automatic transaxle vehicles, also disconnect the throttle control cable.
8. Diconnect and tag all the wire harnesses and vacuum hoses from the cylinder head, intake manifold and throttle body/carburator. Disconnect the spark plug wires, then position them aside.
9. Disconnect the upper radiator hose. Remove the heater hoses from the cylinder head.
10. If equipped, remove the cruise control actuator. Do not disconnect the cable; move the actuator out of the work area with the cable attached.
11. Remove accessory drive belts.
12. Disconnect the inlet hose from the power steering pump and plug the hose immediately to prevent fuild leakage. Remove the power steering pump from the cylinder head and position it aside.

When the power steering hose is doconnected, the fuild will flow out. Cover the alternator with a shop towel to prevent the fuild from leaking into it.

13. If the alternator is mounted to the cylinder head, remove it.
14. Remove teh powersteering and alternator brackets if they are mounted ton the cylinder head.
15. Remove the distributor. Be sure to scribe a line relating the position of the distributor to the engine for easy installation.
16. If equipped, remove the cylinder sensor next to the distributor.
17. Remove teh valve cover.
18. Remove teh timing belt.

Do not crimp or bend the timing belt.

19. Remove teh exhaust header pipe nuts and the header piipe bracket (if equipped). Pull the pipe away from the exhaust manifold.
20. If equipped, remove the EGR crossover and air suction pipes.
21. On Accords through 1989 and Preludes through 1991, the cylinder head can be removed with the intake and exhaust manifolds either still attached or removed. On other models, the manifolds should be removed first.
22. On some engines, it will be necessary to remove teh camshaft holders, camshafts and rocker arms to access the cylinder head bolts. If so, refer to the proper procedures in this section.
23. Remove the cylinder head bolts in sequence (take notice of any bolt holes accupied by longer bolts). Failure to follow this procedure may cause the head to warp.
a. On 1984-1989 Accords and 1984-1991 Preludes, work from the ends toward the center. Loosen each bolt about 1/2 turn each time and make several passes to release the tension evenly.
b. On 1990-95 Accords and 1992-95 Preludes, follow the loosening sequence shown on the illustrations. Loosen each bolt about 1/3 turn each time. Repeat the sequence until all bolts are loosened.
24. Remove the cylinder head. The head may resist removal, even with the bolts out. Tap the edge of the head with a plastic or rubber mallet; lift the head straight up to remove it.
25. Remove the cylinder head gastket and clean the mating surfaces.
26. If applicable, remove the intake and exhaust manifold from the cylinder head.

To install:
27. Install a new head gasket on the engine, making certain it is positioned correctly. The cylinder head dowel pins and the oil jet must be in place. Refer to the illustrations if necessary.
28. Install the head. Lower it straight down onto the block, aligning it correctly.
29. Apply clean engine oil to the bolt threads and the contact face of the bolt head. Install the head bolts finger-tight.
30. On all models except 1988089 DOHC Preludes and 1992-95 Preludes with 2.3L and VTEC engines, tighten the head bolts following sequence A. On 1988-89 DOHC Preludes, use sequence B. Use sequence C on 1992-95 Preludes with 2.3L and VTEC engines.
a. On 1984-89 Accords and 1984-91 Preludes, tighten the bolts in two passes. The first pass should bring the bolts to about 22 ft. lbs. (30 Nm). On the second pass, tighten the bolts to thier final torque of 49 ft. lbs. (68 Nm).
b. On 1990-93 Accords, tighten the bolts to 29 ft. lbs. (40 Nm) on the first pass, 51 ft. lbs. (70 Nm) on the seconf pass, then tighten the bolts to thier final torque of 72 ft. lbs. (108 Nm).
c. On 1994-95 Accords and 1992-95 Preludes, the bolts are also tightened in three passes. Tighten the bolts to 29 ft. lbs. (40 Nm) on th efirst pass, 51 ft. lbs. (70 Nm) on the second pass, then tighten the bolts to thier final torque of 72 ft. lbs. (100 Nm).
31. If applicable, assemble the intake and exhaust manifolds to the head. Use new gaskets.
32. If applicable, install the cam, rockers and camshaft holders.
33. If equiped, install teh EGR crossover and air suction pipes.
34. Connect the exhaust pipe to the manifold using new nuts.
35. Install the timing belt.
36. Install the valve cover.
37. Install the cylinder sensor (if equipped) and the distributor.
38. If applicable, install the alternator.
39. Install the power steering pump, then connect the inlet hose to the pump.
40. Install the accessory drive belts. Adjust the belt tensions.
41. Install the heater hoses.
42. Install the cruise control actuator if it was removed.
43. Connect the spark plug wires. Connect all the wire harnesses and vacuum hoses to the cylinder head, intake manifold and throttle body/carburetor.
44. Connect the throttle control cable and/or accelerator cable at the throttle body.
45. Connect the fuel lines.
46. Install the brake booster, PCV and charcoal canister vacuum hoses.
47. Install the air cleaner and intake duct.
48. Refill the engine coolant. It is recommended that the engine oil be changed whenever a cylinder head is removed.
49. Connect the negative battery cable.
50. Start the engine, allowing it to idle. Bleed the cooling system. Check the work area carefully for any signs of fuild leakage or any indication of the timing belt rubbing or slapping the covers.

Sequence A:

8 6 2 4 10
9 3 1 5 7

Sequence B:

7 3 2 6 10
8 4 1 5 9

Sequence C:

9 5 1 3 7
8 4 2 6 10

This is all copied from Chilton's Manual for Accord/Prelude 1984-95

If there is something being refered to that you need, just let me know. I'll look it up and add it.

hondaman23 · 08-03-2002, 06:09 PM

um, is there any way to keep this archived, or faq or something relavent, so that it is easily accessible when any of us need to do work involving the head or whatnot?

89PreludeSi · 08-04-2002, 02:12 AM

im still deliberating if i need to even do the gasket... i have good compression and i havent lost any oil or coolant.... i've been told that the radiator fluid could be white because off rust... but i dunno..
ill replace it just for the hell of it anyways..... thanks for the info though

hondaman23 · 08-04-2002, 08:55 AM

nope, rust won't make it white. no coolant will make it white(only water), and then it gets frothy. check your oil and see if you have any white scum on the dipstick. if you have oil in your coolant, it will be an oil slick on the top, at the rad cap. if you have coolant in your oil(i know, small but big diference) then it would make the oil cap white, and the dipstick would have white froth on it. it seriously sounds like you have something else the matter, like someone forgot to drain the rad flush out or something. do a really good flush. check your thermostat, and put coolant in. also, amke sure you have th esystem bled properly. also, according to your original post, it boils over? it sounds like your thermostat is ****ed up, and whoever had ti last just had water running in it, so it woule be only white, and it would froth and boil over cause there is nothing in it to keep it from frothing and bouiling over(coolant does that)

89PreludeSi · 08-04-2002, 02:31 PM

i ran the hose through the system, with bleader open, drain plug removed, so fresh water was curculating..... i did this for about 30mins and then lets its all drain out, then i added 50/50 coolant and water and its still turned white.... so im assuming the oil is getting in the coolant, but because of the pressure difference between oil and coolant, the coolant isnt getting into the oil.... so before the month is over i plan too do the head gasket