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Discussion Starter #1
Hi all. Have an 84 with stock engine. Noticed coolant was in my oil - think chocolate milk :eek:mg:. Pulled the head and sent to machine shop to test - internal crack. Surfaces looked fine so I'm hoping the block is fine. Anyone know any good shops/resources that sell and ship reconditioned heads? Or has a new one just lying around :grin:. Googling I found one shop - ramscyl.com, but has mixed reviews. I'd prefer not to roll the dice at the junkyard. Any thoughts are appreciated. Thanks!!
 

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cracked head

Can the original not be fixed?
Although who would want to risk it.
There are places around that have the odd head about, if Honda had one spare would cost you a fortune there was one recently but long gone.

Other than that it is a case of pulling heads from junkyard and having them checked.

As the block is in good condition it's an easy fix if you can find the head.

Can you post a picture of the top of the block so we can see if it's a early type engine or later, as depending on the two we can suggest some different model Honda's that will have the same head gasket fitment. For example you could use a head from a 2G accord if you use it's inlet manifold and downdraught carb which you can replace with a Weber 38/38 or 32/36 or if it's a later model engine you can use 3rd Gen Accord head and manifold etc.
 

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Thanks rjudgey! It's at the shop now, so I'll take some pics Monday and post. I'm hoping a replacement head does not also lead to having to swap out the carbs as I just had them rebuilt last year, but I respect the fact that I'm dealing with a 32 year old car so parts/options are limited.

Help educate me please - what could cause a head to crack? Is the most common cause running hot? Since I see junk yard diving in my future, want to arm myself with spotting red flags. I.e. If the junk car shows signs that it overheated (coolant splatter under the hood, busted hose, etc.), I probably want to pass even if that head would test fine now, likely to crack at some point. If the answer is - dude, it's an old car - you're rolling the dice either way - that's good to hear too ?. Thanks!!
 

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Discussion Starter #4
Also, when I replace, I want to make sure I solve the underlying problem, not just the symptom. Thanks!!
 

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cracked heads

Aluminium although light and having great cooling properties has draw back it must be maintained properly on servicing in all aspects whether regular oil changes but also coolant changes but also regular timing checks too.

Most common reason a head cracks is due to the Dizzy being replaced and bolted back on way too advanced causing pinking, pinging or technical term detonation. These pre ignition explosion before ignition takes place causes havoc inside an engines combustion chamber and cylinders, it can melt pistons, crack pistons, and crack cylinder heads from the chamber to inside the coolant and oil passages.

The other common issue with Ally heads is lack of coolant change or complete lack of antifreeze. If some careless owner can't be asked to use anti freeze and just uses bog standard plain water this causes the aluminium and iron in the block to corrode and the added heat speeds this process up, some people in hot countries think that it doesn't get cold no need to have anti freeze or they just have a slow leak from the pipes or radiator that they can't be asked to fix so just top it up with water, eventually the water has no anti freeze and just pure water and over time this erodes away the engine inside out and causes the iron to rust and this mixture running around inside the engine also makes the ally corrode and become soft and porous.

So not much you can do about the above if it's in a place you can get to there is possibility that the head can be welded for instance if the cracks are in the cambers between valve seats they can be ground out a bit and rewelded with new Ally but this can cause weak spots and on a tuned engine could come back and crack later on, but if you were just using it for low miles and didn't rag it often I'd probably attempt a repair as it's doesn't really cost too much on grand scheme of things but as I said does depend where the crack is. As yours is leaking water into oil I'd say it's probably toast and sounds more likely to be an issue with corrosion possibly but hard for me to say without inspecting it closely myself.

So tips for junkyard hunting.

Don't always assume that because the cars a beater that the engine is in bad shape, I've had some pretty poor engines out the scrap yard and they've turned out to be in good shape.

Main thing is obviously mileage, lower the miles the better, unscrew oil filler cap and make sure you have a very bright LED torch to shine in, make sure the oil is good colour not thick black tar that's gone black, or dark red this indicates it's never been serviced when it should and for too long a period of time. If engine has seen a lot of heat you'll notice a very golden tinge to the inside of the engine, a light gold tinge I would say is normal for hot climate but if your hunting in cooler climates then it should be nice and clean like the shots of my cylinder heads I've posted on here. Nice clean oil colour over all inside of the head and rocker cover. Check the coolant in the expansion bottle and radiator if it's got proper anti freeze, either nice bright blue, green or pink colour that's a good sign if its full of rusty water that's bad news. If no water just tip out the contents of expansion bottle if that's full of dried up rust dust not good if it's fairly clean good.
 

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Cylinder heads

BTW try these guys they've had older Honda engines for a little while and even have a picture of Honda Prelude head on their site may have some old stock still left lying around worth a phone call at least. But please take a shot of the top of the block so we can see if you have early or late type engine.

http://jisengine.com/eng_pdt.htm
 

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Discussion Starter #7 (Edited)
BTW try these guys they've had older Honda engines for a little while and even have a picture of Honda Prelude head on their site may have some old stock still left lying around worth a phone call at least. But please take a shot of the top of the block so we can see if you have early or late type engine.

http://jisengine.com/eng_pdt.htm
Wow! I think you are my new best friend!

First, let me say thank you for taking the time to write such a detailed response! I know it is was late where you are when you wrote. Hope you were at least enjoying a nice beverage! Cheers!

So I think you are spot on with corrosion. I purchased the car last year. I was psyched that it had relatively low miles (143K), but that was because it sat a lot (carb issues needing rebuild) and there was rust in the coolant. Looks like a coolant host busted at one point as there we some rust splatter under the hood. Both were addressed immediately, and I haven't seen a recurrence of rust since, but it sounds likely already was too late. My hope is that I don't have unseen corrosion continuing in the block. I'll have to gamble on just replacing the head and if down the road the block craps out, hey, at least I'll have other options for engine swaps! Who needs money anyway! :)

Will definitely be calling your reference on Monday. My preference is to find reconditioned or new/old stock if possible, leaving junk yard search as plan b. Also, the chances of finding a local junk yard that has one is looking slim to none, so then it becomes a matter of trust that they honestly represent their stock to ship me.

Will post pics Mon. Here is a pic under the hood with engine number in view (ET2)...mostly posted to see if I have creds yet to post pics.

 

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Damn a cracked head sucks, I feel for you man. Good luck with finding a replacement :(
 

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The engine is assembled is angled 60 ° V12 type with completely new 48 valves, power capacity of 6.5L for 690 hp (700 PS) at 8250 rev / min and 690 Nm of torque at 5,500 revolutions / minute . Engine block weighs only 235 kg.

This engine is integrated on the Aventador, the power from the engine combined with semi-automatic gearbox 7-speed ISR (Independent Shifting Rod) for time shifting should only take 0.05 seconds Aventador LP 700-4 accelerates time from 0-100 km / h in just 2.9 seconds. 0-200 km / h in just 8.6 seconds. The maximum speed reached 350 km / h.
 

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Engine V-born not only solved the problem of the cylinder increases beyond 6 but also giving more auto engine features precious. There's even some xiklanh that only 2 or 4 people also used the V-engine trend V motors used for this kind of premium passenger cars as expensive as Lexus GS400 (V8), Toyota Camry Grande (V6), Ford Escape (V6), BMW 5 Series (V8), Mercedes-Benz SL55 AMG (V8), Ferrari 550 Maranello (V12), DB7 Aston Marting (V12) ?? has brought this model features power and great speed.
 

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Discussion Starter #15
Pics

BTW try these guys they've had older Honda engines for a little while and even have a picture of Honda Prelude head on their site may have some old stock still left lying around worth a phone call at least. But please take a shot of the top of the block so we can see if you have early or late type engine.

http://jisengine.com/eng_pdt.htm

Hi friend. Here are some pics of the top of block and engine #ET2-1539803. # on plate behond left headlight matches on block (hard to see), so we know it's original. Take a look and let me know what you think. Thanks!!







 

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Engine

It's definitely an early type ET not A18 which is a shame as the newer A18 would have given you some interesting options for high compression 2.0 conversion using the same head and carbs. Can be done on yours but only if you can find the right felpro head gaskets and provided your block isn't severely corrode. On the plus side does take many years for cast iron to rust through! lol! aluminium can go soft quite quickly.

It's a shame as the inside of your head looks in pretty reasonable condition bit of cam bearing wear though which with your miles is pretty normal.

JIS are really good dealt with them before they also good source for pistons and bearings if you need replacements. They probably even have blocks as well, if you needed a new engine I would ask them for a A20 short block and a A18 head match those two and you end up with a super high compression 2.0l engine that will run on your existing ignition and Carb setup. Combine that with header, exhaust and mild camshaft and you easily get around 140-150bhp.
 

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Discussion Starter #18
It's definitely an early type ET not A18 which is a shame as the newer A18 would have given you some interesting options for high compression 2.0 conversion using the same head and carbs. Can be done on yours but only if you can find the right felpro head gaskets and provided your block isn't severely corrode. On the plus side does take many years for cast iron to rust through! lol! aluminium can go soft quite quickly.

It's a shame as the inside of your head looks in pretty reasonable condition bit of cam bearing wear though which with your miles is pretty normal.

JIS are really good dealt with them before they also good source for pistons and bearings if you need replacements. They probably even have blocks as well, if you needed a new engine I would ask them for a A20 short block and a A18 head match those two and you end up with a super high compression 2.0l engine that will run on your existing ignition and Carb setup. Combine that with header, exhaust and mild camshaft and you easily get around 140-150bhp.

Yeah - was definately interesting seeing the head out in the open. Maybe hard to see from the earlier pic but the black marker lines on the tip of the head show where the cracks (plural) are - looks like on top of cyl 3 and 4, on the side where the coolant in/out ports are. The "D" shaped coolant port looked a bit nasty, so definately looks like corrosion was the culprit here.

Now I'm having some fun matching up a replacement head. Seems Honda made a few casts for that year. Mine is PC7C...with number under it HF-C...see pic below:



found this one on eBay - in case JIS doesn't have the right one. I really hope they do because I'd like to buy from a recommended shop. Plus, I liked the fact that since my core is cracked, they didn't want it...so a head I would buy from them should not have any crack repairs!

http://www.ebay.com/itm/201538943845?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Same cast #, but the bottom number is HF-A. Looked at all angles and fitment seems the same...so I'm guessing the "A" may mean built in a different plant? Is it the case as long as the cast # matches, I'm golden? Finding other oddities with Honda numbering. Per service manual the first digit after the ET2 is the year. The number 3 should be 1984..would think it would be a 4, but I digress. Mine is 1. Maybe the dude in charge of numbers in the 80's had too much sake! :)

Thanks again! BTW - what is your name? Do you need any spare parts? I have a box of misc stuff and would like to share if you're in need as you certainly helped me a lot here!!
 

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It *looks* to be suitable, but I'd wait for another member to fully confirm that head will work.
 

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I'm pretty sure the Ebay one will work. I really don't think that listing is actually for an Accord. The intake port spacing matched the Prelude and I'm pretty sure it's a unique pattern. '84-'85 Accords had even spaced intake runners, and prior to that the heads had intake & exhaust on the same side. I'll go look at my extra heads and see what HF-x they have.

Also, JIS is good and I second the recommendation. I bought a long block from them a few years ago and it was top quality.

As far as the ET2 # thing, where did you get that information? The service manual says that everything after the engine code is just a serial number. To my knowledge the only place date information is held is in the VIN.
 
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